My other history related articles

Here are links to other articles I have written for Ancient Warfare. 

This was the original presentation of the crowd-othismos.  As you can see in the last article this concept has matured.

'The Aspis: Surviving Hoplite Battle'. Illustrated by Johnny Shumate: http://www.karwansaraypublishers.com/cms/karwansaray/ancient-warfare/about/readmore-aw/13-ancient-warfare/ancient-warfare-issues/31-ancient-warfare-i-3.html

I compiled all the evidence I could find for both Linen and Leather as the material used in the "linothorax." 

‘Don’t get stuck on glued linen’: http://www.karwansaraypublishers.com/cms/karwansaray/ancient-warfare/about/readmore-aw/13-ancient-warfare/ancient-warfare-issues/49-ancient-warfare-iv-3.html

This was a labor of love.  An article on Xanthippus of Sparta whose leadership halted the advance of a nascent Rome and left a lesson for Hannibal on how to destroy a Roman army. 

'Regulus' demise'. Illustrated by Carlos de la Rocha and Igor Dzis.

The fate of nations is often decided on battlefields and the course of battles may be decided before they are fought by the tactical genius of great generals. History's foremost military commanders led their people to conquest or fought to stave off being conquered. They fought as usurpers or championed freedom and spread ideologies. Rarely in history have leaders altered the course of history solely for that purest of motives: profit. Xanthippus of Sparta was one such man.

http://www.karwansaraypublishers.com/cms/karwansaray/ancient-warfare/about/readmore-aw/13-ancient-warfare/ancient-warfare-issues/39-ancient-warfare-iii-1.html

The Storm of Spears and Press of Shields

I received the OK from Jasper at Karawansaray Publishing to post my full article on hoplite mechanics as it appeared in the Marathon special issue of Ancient Warfare: http://www.karwansaraypublishers.com/shop/the-battle-of-marathon-special.html

Over the last half century, a schism developed over hoplite combat that has devolved into a bellum sacrum, with an orthodoxy assailed by an increasingly popular heresy.  The orthodox position, championed by Hanson, Luginbill, and Schwartz, portrays hoplites as lumbering masses of men that charged directly into each other and contested the battlefield by attempting to physically push their foes.  Van Wees, Krentz, and Goldsworthy, describe hoplites as closer to skirmishers, fighting in an opened order, and often paired with missile troops.  Any “push” was either a figurative description or uncoordinated shield-bashing.  I believe they are both in some measure correct, and often equally wrong, because this debate has forced historians to stray far from their fields of study.  Their arguments suffer from an insufficient understanding of the physics and mechanics of large masses or crowds.  Group behavior is my field, and, with the context that I can provide for their arguments, I shall make an attempt at syncretism.

Herodotus, writing in the mid 5^th century, was the first author to describe the heavy infantry of ancient Greece as hoplites, or men who were considered fully equipped for battle.  In his day, a hoplite’s arms and armor, his panoply, might have included a bronze helmet, greaves, a bronze cuirasse or corslet of leather or textile, and an iron sword.  A rich man might add bronze thigh, upper arm, ankle, and even toe guards.  The only pieces that seemed to have been required were the large, round shield or aspis and a 1.8-2.5 m thrusting spear.  Herodotus contrasts hoplites with psiloi, literally “naked”, armed with missile weapons.  By the time Herodotus wrote, hoplites fought in a formation termed a phalanx by modern authors, following Homer’s use of the term in relation to massed combat.

The panoply of the hoplite emerged in the late 8^th century, with the advent of the round, domed, shield and thrusting spear with pointed spear-butts, or sauroters.  It has been suggested that these items indicate a break from earlier, skirmishing and missile combat, but aspis bearing hoplites on some early vases, like the Chigi vase (ca. 640), appear to bear a pair of spears with throwing cords attached, a shorter one most likely to be thrown and a second longer spear which could be thrown or used in close combat.

By the 5th century, the classical Greek dory, or fighting spear, appears to have been as much as 2.5 m long, but it was effectively longer because a combination of rear weighting and tapering of the shaft moved the center of balance, hence the grip, back to about a third of the way from the bottom. A 2.5 m dory had a reach of over 1.5 m, similar to a 3.3 m mid-balanced spear.  The great reach of this spear was a handicap in single combat, because it would be useless if a foe managed to move up shield to shield.  A man cannot reach back far enough to bring a point that is 1.5 m from his grip to bear with any force against a foe this close.  However, in a battle line, the extra reach enabled hoplites to overlap their spears and support the men beside them.  Moving within the reach of the combined spears of a phalanx would be much more difficult than evading any single spear.

The shield has also been seen as unsuitable for single combat.  The hoplite’s shield, the aspis, hoplon, or perhaps most specifically, Argive aspis, varied little in size or shape over the whole period of hoplite warfare.  It was made in the form of a flattened dome, some 10 cm deep, between 90 cm to just over a meter in diameter, including a robust, offset rim of some 4-5 cm.  The rim, and often the whole face of the shield were covered in a single sheet of bronze, 0.5- 1 mm thick.  The orthodoxy reconstructs this shield as exceptionally heavy (7-9 kg), but Krentz has suggested a more likely 6.8 kg or less.

These features are not unique to the Greek shield.  A convex shape functions to transfer force away from the site of impact, while an offset rim reinforces the face of the shield so that it does not split when struck.  Exceptionally convex shields, conical in profile, are common in many cultures because the profile ensures that an incoming strike will encounter a sloped shield-face. 

The aspis had an uncommon system of grips that some suggest limited the shield’s utility in single combat to the point that men were forced to fight in close order.  The left arm was slipped through a bronze cuff, or porpax, placed either at the shield’s center or just to the right of center.  The porpax either accepted a leather sleeve or was itself tapered to accept the forearm up to just below the elbow, and fit like the cuff of a modern artificial limb, holding the limb so snuggly that the shield would not rotate around the forearm.  A second grip near the rim of the shield was gripped by the hand, and tension from this grip acted to hold the arm in the porpax.  In shields from other cultures that have a double-grip system, the grip for forearm and hand usually flank the center of the shield.  This allows most of the shield to be brought up in front of its bearer, while the aspis allows only half the shield to cover a man’s front.  The central placement of the porpax in the aspis is an advantage because it makes holding the shield up on the bent forearm easier by reducing the proportion of the shield’s mass that is to the right of the elbow and must be pivoted up.  A double-grip limits the range through which a shield can be moved to block.  The shield cannot be held as far away from the body as one gripped by the hand, which leaves a greater portion of the body vulnerable to incoming strikes and reduces the distance a strike must penetrate to wound.  It has been suggested that hoplites could gain coverage by standing perpendicular to shields in a “fencers” stance.  This analogy is untenable because fencers lead with their weapon hand, while hoplites would have to come up parallel to their shields to effectively strike with their spears. 

The aspis has one unique feature that is difficult to explain.  The Bomarzo shield in the Vatican’s Museo Gregoriano Etrusco, which retains large portions of its wooden core, presents an odd picture.  The shield’s core is only 5-6 mm thick over much of the shield’s face, thickening to 8 mm in the center where the porpax was affixed.  Near the rim of the bowl, the shield curves back sharply to form side-walls of 10-14 mm that taper towards the shield face.  

A shallow dome tends to spread outward under pressure, and the wide, perpendicular rim acts to keep the face from splitting.  Under pressure, an aspis will fail where the side-wall and the face join.  This odd profile has inspired the suggestion that the aspis’s great weight required this curve to allow a man to carry the shield on his shoulder.  Leaving aside that the aspis’s mass has probably been overestimated, some rough calculations show that this explanation is unlikely.  The aspis’s weight did not likely motivate the curved outer portion because, even though only 3-4 cm wide,  the greater thickness and large diameter of the “ring” of wood that makes up the side-wall section accounts for 20-40% of the total mass of wood making up the shield-face!  Reinforced side-walls could provide added protection against chopping blows by swords, but this would be superfluous given the thick, bronze covered rim.  The side-walls appear to add more depth to the shield than strength, a function we will return to later.

Modern authors present us with irreconcilable images of how these early aspis-bearers fought.  To some there was a “hoplite revolution” and orderly phalanxes either closely follow or predate the new shield.  Van Wees describes a “motley crew” of intermingled hoplites, archers, and horsemen that slowly transitions from bands of warriors to the phalanx familiar to 5th century historians.  Tyrtaeus, a 7th century Spartan poet, wrote to inspire the warriors of his polis.  Two themes run through his works: he chides his audience to stand close to their fellows and to bring the fight to close quarters with their foes.  Tyrtaeus can easily be interpreted as a herald for the classical hoplite phalanx, with close ordered ranks and files.  But if men were formed in an orderly phalanx, why would the poet need to deride skulkers who remained out of the range of missiles? 

This dichotomy of order-vs-chaos is a hot topic in the physical sciences, and the boundary between the two has diminished.  Order within groups can arise spontaneously from seemingly random acts of individuals.  We call this process self-organization.  Through this mechanism, swarms, flocks, herds and schools of animals achieve levels of coordinated movement that any human drill master would envy.  Swarms, or crowds, of humans are capable of this type of organization as well.  If we take van Wees’s “motley crew” and add simple, logical rules like “archers tend to stand behind men with shields” and “men with shields tend to stand beside men with shields to protect their flanks”, then we end up with a formation that resembles the Germanic shield-wall or late Roman foulkon.  This type of formation puts more heavily armored men, who may throw missiles themselves, in front of unarmored missile troops to act as a wall or screen. Segregation like this is natural in tribal war bands, where richer, better equipped men lead a troupe of progressively poorer equipped warriors into battle.  It would actually take more discipline to keep troop types evenly mixed than to clump in this manner.

There is no need for hoplites to form in a particularly opened order to allow men to move freely through such a self-organized group.  One advantage of the large diameter of the aspis is that it acted as a literal meter-stick.  Men did not need to make any judgment on their frontage beyond lining up shield rim to shield rim.  In human crowds, as in schools of fish or flocks of birds, individuals are completely interchangeable. The result is that no one has a specific place in the formation and the group is highly fluid.  Men can move to the front line or beyond to throw missiles at the enemy or challenge a foe, then melt back into the group and retire out of combat.  Such “milling” is commonly seen in all but the densest of crowds.

When two crowds come into contact, the dynamic changes and the presence of one lends order to the other.  The limitation on forward movement and the presence of the enemy line as a focal point for the men in both mobs results in the crowd becoming denser as men pile up.  If the men at the front-line between the groups are shield to shield, then the literal pushing of mass on mass envisioned by the orthodoxy could ensue.  Thus, a crowd like this can be both flexible enough to allow all of the missile combat and personal challenges seen in the pre-hoplite era and spontaneously form into compressed masses akin to phalanxes upon contact with the enemy.  Men who are free to move forward and back are also free to flee at the first setback.  This can be mitigated by forming men up next to their relatives or in smaller units, where leaving would be noticed.  To form the ordered ranks and files that made up the classical phalanx, each man needed to know only who he stood next to or behind

If the economies of the Greek cities allowed for increasing numbers of warriors and a higher percentage of these were well armed hoplites, then a shift from a few ranks of men acting to shield lighter troops to deep ranks of spearmen who charge swiftly to spear range may simply emerge from the conditions of the battlefield rather than result from an intentional tactical shift.  As the number of men increased, additional depth would be easier to coordinate than a widely extended battle line. If the percentage of missile troops dropped low, or the defenses of the hoplites reached a level of protection that charging through an enemies’ missile barrage was less risky than engaging in a missile duel, then the move to an all hoplite phalanx would result.  Once hoplites began to form in more than four ranks, missile troops became ineffective.  Xenophon (Anabasis 3.3.7) describes the difficulty of bowmen in firing over the ranks of their own hoplites.

Increasing the depth of phalanxes is advantageous in close combat for a variety of physical and psychological reasons.  The heretical view holds that the ranks beyond the first one or two do not directly participate in battle, but play an important role in supporting the front ranks in battle.  Beyond acting as a reserve, ready to step forward over the fallen rankers in front of them, the mere presence of these men behind the front rankers raises the morale of those men fighting.  In addition, deep ranks of men formed behind the fighting front limit the ability of those men to turn and run. 

In orthodox view, all of the ranks run together into battle as a single mass, then crash into the formation of their foes.  This physical pushing match, for which the term othismos has been applied,  has been likened to a giant rugby scrum, with the goal of pushing the opposing section of the phalanx out of alignment with the rest of the formation until they rout.  I believe that a pushing match did occur in hoplite battle, but I am sympathetic to the heretics because the physics of othismos have been misstated by the orthodoxy.  

Othismos was a noun that derived from the word otheo, a verb meaning “to thrust, push, or shove”.  The modern definitions of othismos treat the noun othismos as a verb, for example Liddell and Scott render it as either “thrusting, pushing” or secondarily “jostling, struggling”.  As a noun, the word would have to be defined as “a state wherein thrusting, pushing, jostling or struggling occurs”.  We commonly call such a state a dense crowd.  Perhaps the best English equivalent would be the way we derive a state of dense crowding, a press, from the verb “to press”.  This is not a crowd in the sense of many people or a throng, because the Greeks had other words to describe that.  It is essentially a traffic term, like jam or deadlock, implying that many individuals are locked together and cannot move past.  Crowds can “push” with extreme force, but the word focuses on density, more of a squeeze directed within the group than without. 

The term “Othismos” had three common uses.  First, it is used to describe hoplite battle.  Thucydides (4.96.2) describes fierce combat, noting that it is accompanied by “othismos aspedon”.  This description has been held up as the clearest evidence for othismos as “pushing with shields”, but perhaps a better reading is a “deadlock of shields”, emphasizing the crowding of the opposing ranks together, with or without pushing.  Arrian (Tactica 12.3) used the same word to describe not opposing ranks, but the crowding of second rankers in a phalanx against the backs of the front rankers, after which they can reach the enemy front rankers with their swords.

 Second, othismos is used is in situations familiar to anyone studying crowd disasters.  In the worst of these, people are asphyxiated or squeezed either hard enough or long enough to cause them to lose consciousness or die because pressure on their chest and diaphragm prevents them from breathing.  Xenophon (A. 5.2.17), Plutarch (Brutus 18.1), and Appian (Mithridatic wars 10.71) all describe othismos occurring as a crowd of men attempt to exit a gate.  Polybius (4.58.9) describes the Aegiratans routing the Aetolians who fled into a city: “in the confusion that followed the fugitives trampled each other to death at the gates…Archidamus was killed in the struggle and crush at the gates. Of the main body of Aetolians, some were trampled to death…”  It is a maxim that most deaths attributed to trampling are in fact due to asphyxia while still standing. 

The third use of othismos occurs where literal pushing could not occur.  When Plutarch (Aristides 9.2) describes ships in othismos, he refers to crowding, not mass pushing.  In many cases, “othismos” is completely figurative.  Herodotus twice (8.78, 9.26) uses othismos to describe an argument.  This is often translated as a “fierce argument”, but traffic terms are commonly used to describe arguments.  For example, we regularly call for an arbiter when two sides in negotiation come to an impasse or a log jam.  At Plataea, the Tegeans and Athenians (Herodotus 9.26) found themselves at an impasse in negotiations because they both put forth equal claims to an honored place in the army’s formation.

The definition of othismos does not of itself require a coordinated push of all ranks against an enemy formation, but I believe there was such a concerted struggle of mass against mass.  The orthodoxy portrays hoplites as charging as much as 50 m in order to impart what Schwartz termed “a maximum of penetration power at the collision”.  However, the whole notion that hoplites charged like un-horsed medieval knights to maximize the mass’s force during a collision is a fallacy.  It takes only a few yards to achieve “ramming speed”, and any excess distance causes fatigue and loss of cohesion. They would be correct if the goal was to maximize the force of one man colliding with another, but the physics of maximizing the aggregate force of a group of individuals is different.  Dense packing is far more important to transfer a strong, sustainable force, even if it occurs at slow speed.  If a hoplite phalanx charged directly into a pushing of match, it would have closed up all of the men in the files belly to back in the manner I have previously described (Bardunias 2007) and charge from very short range to minimize the loss of cohesion.

The common description of othismos as a tug-o-war in reverse leads to some false impressions.  The image conjures up men standing perpendicular to their foes, digging in the edge of their rear foot as they lean into the man in front with their shoulders in the bowls of their shields.  But in a tug-o-war, the force is transferred through the rope and men can take any stance as long as they pull on the rope.  This is not the case with files of men pushing.  As men in files pushed against those in front, the force first acted to compress the men in front, and only after they resisted compression could force be transmitted ahead.  At moderate levels of compression this was not a problem, but as greater force was transferred forward, the men could no longer hold their shields away from their bodies and shields became pressed to the torsos. 

If men were standing in a side-on stance as portrayed by the orthodoxy, the force would be transferred directly through the shoulders of each man in file.  This was unstable because the only thing holding men perpendicular to their shields was the strength of their left arm.  Unless the men closed up laterally belly to back, which is impossible with a meter-wide aspis, the sustained, grinding pressure on their right shoulders would force them to collapse forward until they were parallel to their shields and the men in files were packed belly to back.  Once they achieve this spacing and stance, they can be compressed no further and have achieved what specialists on crowd disasters term a “critical density”.  This is defined as at least 8 people pressed together with less than 1.5 m of spacing per person. By simply leaning against the man in front like a line of dominoes, 30-75 % of body mass can be conveyed forward in files, and just three leaning men can produce a force of over 792 N or 80 kg.  Shock waves can travel through such crowds, and less than 10 people have been shown to generate over 4500 N or 450 kg of force. 

This has been misunderstood by authors in the past.  To counter the objection that the force transferred forward by men in files would be lethal to one’s own file-mates, Franz, as quoted by Schwartz, mistakenly put forth that force is not derived from the weight of them men in file, but from their muscular strength in pushing.  This is not true.  He further quotes Franz as describing why the files did not produce lethal pressure: “When people behind sense that pushing does not produce an immediate advantage, they stop pushing.  This results in a kind of reverse thrust.”  This is surely true for most historical armies, where weapon play, not pushing is the goal, but the whole point of othismos as defined by the orthodoxy is to push against the opposite formation with the greatest force.  A file of hoplites, even 8 deep, could produce enough force to kill a man through asphyxia.  A force of 6227 N will kill if applied for only 15 seconds, while 4-6 minutes of exposure to 1112 N is sufficient to cause asphyxia.  Hoplites would be purposefully attempting to create and maintain levels of pressure that occur accidentally in crowds.  Killing crowds form when people try to move in a specific direction, such as towards a stage or out a door.  Hoplites pushed ahead in file, and if whatever was in front of them did not give way, pressure would rapidly build to lethal levels, and by simply leaning forward they could maintain much of this force for extended periods. There is no requirement for containment such as walls alongside the crowds as we usually see in disasters.  As long as they are pushing towards a common goal, in this case directly toward the enemy through the back of the man in front, they will not disperse laterally. 

The heretics would be correct in assuming that pushing by deep files was not survivable, but for one detail.  In my description of the hoplite shield, I put off discussing the single feature of its construction that appears to be unique - the oddly thickened side-walls.  As I noted, it appears to primarily add depth, not strength, when compared to other convex shields.  It is this depth that allows a man to survive the press of othismos, by protecting his torso from compression.  To do so, it would be held directly in front of the body with the top right half of the shield resting on the hoplite’s upper chest and the front of his left shoulder, the bottom on his left thigh.  Most of the men in files would have been standing upright and leaning forward.  Only the rear few ranks had enough freedom of movement to assume positions that are compatible with active pushing.  Shock waves of the combined weight of the file would be added to the pushing force in the rear rankers in the same manner that the mass of a battering ram is pushed towards a barrier.

Othismos may have originated because men pushed their foes away from fallen leaders to retrieve their corpses and armor.  Such struggles are common in the Iliad, and Herodotus used the word othismos to describe the struggle over Leonidas’s body at Thermopylae (7.225).  In what may represent an egalitarian shift, victory in hoplite battles generally went to the force that held the battlefield and the bodies of all the fallen men upon it. This could represent a ritualization of warfare, and a means of deciding conflict that minimized slaughter, but it may have been the most efficient means of combat given a preexisting warrior ethos that called large decisive battles and the retrieval casualties.  Pushing would have evolved gradually from close-in fighting that predated the aspis.  Mass pushing is not unseen in other settings.  For example, the Romans pushed with bosses of their shields Zama (Livy), but the shape of the scutum limited the maximum force that could be generated without killing their own men.  A sub-lethal, jostling, shoving crowd must have existed before the aspis became specialized for killing crowds.  Also, the threat of battle moving to a lethal crowd phase would justify the shape of the shield, even if othismos was not the goal of combat.  The shield as “life preserver” in a killing crowd explains the constancy of the shape over time.  The deep, flattened dome could not vary much and still retain its ability to resist compression.  When the shield was found inadequate protection from missiles, an apron of leather was hung from the round shield rather than remaking the shield into a weaker oval that would provide the same coverage.

The remainder of this article describes the course of hoplite battle in Herodotus’s day, reconciling orthodox and heretical views where possible.  Athenian hoplites, like those of most poleis, called up amateur levies according to tribal units called taxeis of about 700-1000 men, which was then subdivided into lochoi of 100 or more.  The men may have not had set places in ranks, but by this date they probably knew who they stood next to.  These taxeis were drawn up alongside one another to form what Thucydides called a parataxeis and others call a phalanx. Spartans provide us with an example of what was possible with a professional army.  Their basic tactical unit was the sworn band or enomotia of about 40 men, wherein each man knew his assigned place.  Ancient authors usually recorded the number of ranks, or shields, men formed in.  This seems to have often been up to the unit commander, and could commonly vary from 4 to 16, with 8 or 12 being the norm for most of the period.  Environmental constraints, like a narrow road, could force units to form in deep ranks by stacking smaller units.  Thebans in the late 5th and early 4th century notoriously formed in 25 or even 50 ranks for major battles, an obvious advantage for their contingent, but their allies attempted to limit them to 16 ranks in the Corinthian war because the sacrifice in frontage left the whole phalanx vulnerable to envelopment.

Once the men were in place, in most armies their leaders would walk along the front haranguing them.  Spartans relied on encouragement between hoplites and sang to each other in the ranks.  In a prelude to the battle to come, the opposing light troops or cavalry could skirmish in the space between the opposing phalanxes.  When the light troops had been recalled and the sacrifices had been taken, the commanders had trumpets, salpinx, sounded and men began marching towards the enemy.  At this distance men would have been marching with their spears on their right shoulder and their shields on their left.  For comfortable carry, the balance point of the spear should be just beyond the shoulder, and many images show hoplites holding the spear down near the sauroter.  Ancient Greek battle fields were notoriously flat and not overly broad which allowed men to keep some semblance of order.  As they advanced the hoplites sang the Paian in unison, aiding morale and coordination.  Marching in step would have been beyond most armies, but Spartans moved to the sound of pipes to help the men keep pace.  At this point men would bring the shield up in front and the command would be passed for the first two ranks to lower spears.  This has been interpreted as bringing the spears down to an underarm position, but hoplite reenactors have discovered a simple maneuver to “lower” a dory into the overhand position.  They let the spear fall forward off the shoulder while at the same time bringing the rear of the spear out and up.  There would be no need to shift the grip later if overhand strikes are desired.

When the armies were less than 180 m apart, most phalanxes shouted an ululating war cry to Enyalius and charged at the run.  They did so for psychological reasons, both to channel their nervous tension into the attack, and frighten the enemy with their rapid advance.  Coordinating the charge along the chain of units that made up the phalanx seems to have been difficult, and gaps often formed as some hoplites charged sooner than others.  Variation in speed of advance could lead to one section of the line leaving the rest running to catch up (Xenophon, Anabasis, 1.8.18).  Spartans did not charge at the run, but approached in a slow, orderly fashion, so any unit ranged alongside them invariably pulled away when they charged.  The result is that a phalanx rarely encountered its opposite as a unified front.  For these reasons Thucydides (5.70.1) tells us that large armies break their order are apt to do in the moment of engaging.

Thucydides (5.71.1) also describes phalanxes drifting to the right as they advanced because men sought to shelter their unshielded right side. This would have resulted from men twisting their torsos to hold the aspis in front of them.  But it is likely that the whole phalanx contracted as well.  Bunching as they moved would have been a natural reaction of frightened men as it is with other animals.  The Strategikon, attributed to Maurice (12B.17), describes the ease with which men can converge laterally just prior to contact with the enemy.  Two approaching phalanxes would end up overlapping on the right through either drift or contraction to the right, and the difference would be difficult to tell.  Men who began the charge at a spacing of just over the diameter of their shields might now find that they overlap to some degree with their neighbor’s.

Much of the order lost during the charge could be regained as units reformed a battle line upon contact with the enemy.  The alternative is that whole taxeis ran tens of meters past units next to them in line that were engaged when the foes opposite were delayed or slow moving Spartans.  The two phalanxes would have slowed as the enemy loomed large.  The same fear that drove them to charge would keep them from running blindly into a hedge of enemy spears. Because disorganized men charging at speed into the enemy results in a weaker mass collision, there is no reason why men could not halt at spear range rather than after crashing together.  If men did not regularly stop and fight with their spears, then it is difficult to understand the many references to one phalanx breaking when the two had closed to spear range.  Hoplites converging at even a modest 5 mph would cover this distance in less than half a second. 

What followed was described by Sophocles (Antigone, 670) as a “storm of spears”.  While taunting their foes, the first two ranks of the opposing phalanxes would assume the ¾ stance common to most combat arts and strike overhand across a gap of about the 1.5 m reach of a dory.  The overhand motion results in a much stronger thrust than stabbing underhand (Connolly, 2001), and would be less likely to impale the men behind.  When striking from behind a wall of shields, the overhand strike not only ensured that your arm was always above the line of shields but allowed a wide range of targets.  During this combat adjacent hoplites were mutually supporting, and a man could be killed through the failure of those alongside him (Euripides, Heracles 190).  The second rankers would have attacked where they could reach, but their spears also acted to defend the men in front. 

The aspis would have been tilted up and toward the enemy.  With the shield snug on the forearm, this would be the natural result of lifting the arm, but it also presents the maximum shield area to a downward, overhand strike.  In this position, the shoulder doesn’t bear any of the weight because the centrally placed porpax results in the lower half of the shield balancing the upper half with all the weight on the arm.  It can be braced against the shoulder if pushed back by a strike.

Spear fighting could go on for some time, and often one side must have given way as a result, but we know that battles could move to close range.  It is difficult to imagine men easily forcing their way through multiple ranks of massed spears, but we know that hoplites often broke their spears, and a sword armed man would be highly motivated to close within the reach of his foe’s spear.  Perhaps this was easier as fatigue set in.  Once swordsmen closed with the spearmen somewhere along the line, phalanxes could collapse into each other like a zipper closing as spearmen abandoned their useless spears in favor of their own swords. 

It is now that rear rankers could bring their pressure to bear.  They would close up swiftly, initially supporting those in front, but then gradually pushing them tight together.  All ranks would now cover their chests with their shields.  While this was occurring the front rankers fought, and their blows could not miss (Xenophon, Anabasis, 2.1.16).  Images of hoplites show a variety of strikes that could be used with the upraised right arm over the shields.  The so-called “Harmodios blow” is a high slash from around the head that has been derided as useless, but here strikes and parries up around the head would be the rule.  Point heavy chopping swords would be useful in othismos, but the short swords, often attributed to Sparta and seen on stelai from Athens and Boeotia, would be deadly.  A downward stab, alongside the neck, into the chest cavity can be seen on a vase in the Museo Nazionale de Spina (T1039A).

The crowding of othismos and periods of active, intense pushing could last for a long time as men leaned ahead like weary wrestlers.  But the peak pressure is only maintained if the opposing phalanx chooses to resist it.  If they move back, their foes have to pack-in tight again before maximum force can be transferred.  All such moves have to start at the back of the files, there is no point at which a man could simply jump back and his enemy would fall forward.  Just as packing was gradual, so is unpacking.  The whole mass would move in spasms and waves like an earthworm.  Increased file depth is an advantage in this type of contest, but the answer to those who wonder how why at Leuktra 50 ranks of Thebans didn’t immediately drive 12 ranks of Spartans from the field rests in the difficulty in coordinating such deep files of men to push in unison and the need to constantly repack as men advance.  Deep ranks function more like a wall behind those in front than an aid is pushing forwards.

When hoplites could no longer sustain the rigors of pushing, the rear ranks of the phalanx would turn and flee.  What followed could be a free for all as men broke ranks to target the backs of routed foes.  It is now that lessons of hoplomachoi, martial arts masters, were of most use (Plato, Laches 182a).  Men who had been holding up their arms throughout battle would surely opt for underhand strikes at this point as seen for single combat on many vases.  Hoplites did not press pursuit for long, so many saved their lives by dropping their shields and spears and outpacing those chasing them.  Safer still was making a stand with compatriots and letting the victorious hoplites find easier prey as Socrates did after Delium (Plato Symposium 221b).

Hoplite battle encompassed both the storm of spears and press of shields, but by the late 5^th century clever generals were coming up with ways of exploiting the weaknesses of both phases of combat.  Envelopments and ultra-deep formations took advantage of the weaknesses of armies set on simply fighting a decisive battle with units arrayed opposite them, often with little regard for flank protection.  A century later hoplites would lose their supremacy to Macedonian pikemen, themselves up-armored skirmishers, who presented them with spears that far outranged the dory and only a dense hedge of spear points to push against.

 

Paul Bardunias is an entomologist working on self-organized group behavior in termites and ants.  His interest in ancient warfare is hereditary, for his family comes from Sparta.  He is currently applying his scientific training to provide new insights into hoplite combat at www.hollow-lakedaimon.blogspot.com.  He is indebted to Russian hooligans, whose tireless shenanigans allow us to witness the fluidity and spontaneous order that arises in crowds of belligerent men (http://www.youtube.com/watch?v=dAk4dceoK4&feature=related).

 

J.K. Anderson, Military theory and practice in the age of Xenophon.  Berkeley and Los Angeles 1970

P. Bardunias, ‘The aspis. Surviving Hoplite Battle’, in: Ancient Warfare I.3 (2007), 11-14.

G.L. Cawkwell, ‘Orthodoxy and Hoplites’, in The Classical Quarterly 39 (1989), 375-389.

P. Connolly, D. Sim, and C. Watson, “An Evaluation of the Effectiveness of Three Methods of Spear Grip Used In Antiquity”, in: Journal of Battlefield Technology, Vol. 4, No. 2, July 2001.

A.K. Goldsworthy, ‘The Othismos, Myths and Heresies: The Nature of Hoplite Battle’, in War and History 4 (1997), 1-26.

V.D. Hanson, The Western Way of War. Oxford 1989.

V.D. Hanson (ed.), Hoplites. The Classical Greek Battle Experience. London and New York 1991.

P. Krentz, ‘The Nature of Hoplite Battle’, in: Classical Antiquity 16 (1985), 50-61.

P. Krentz, ‘Continuing the othismos on the othismos’, in Ancient History Bulletin 8 (1994), 45-9.

P. Krentz, D. Kagan and D. Showalter, The Battle of Marathon. Yale University Press (2010).

R.D. Luginbill, ‘Othismos: the importance of the mass-shove in hoplite warfare’, in: Phoenix 48 (1994), 51-61.

L. B. Perkins, Crowd Safety and Survival, Lulu.com, 2005

A. Schwartz, Reinstating the Hoplite: Arm, Armor, and Phalanx Fighting in Archaic and Classical Greece. Franz Steiner Verlag, 2010

H. van Wees, Greek Warfare. Myths and Realities. London 2004.

What exactly is my field of expertise?

Every now and then I get a comment that I feel would be better answered as a post so that any others with a similar question can easily find the answer.  Recently I was asked the following in response to my last post:

"What exactly is your field of expertise?"

I am an entomologist. One might wonder what bugs have in common with hoplites, but I work in a field called Self-Organization. We study how large groups of individuals (ants, termites, and people) come together and produce specific outcomes without the need for specific top-down planning. In social insects, this includes things like building huge nests and digging extensive tunnel galleries (my specialty), but in humans this encompasses the behavior of large crowds and the self-organization of traffic patterns.
It is the confluence of a chance of birth, my great-grandfather was actually from Sparta, and the fact that in war, and especially in a mass formation like a phalanx that we see humans acting in the most self-organized way that brought me to this.

You might say "war? self-organized? but what of all those officers?" I would counter with the fact that no officer in the history of warfare ever ordered his men to rout and run for their lives, and yet they do so in a highly coordinated manner. This same under-layer of self-organization exists during an advance and in group fighters like hoplites, during battle.

Over the last decade I have been studying hoplite battle. Initially I simply bought the prevailing notions of V.D. Hanson and those on his side of the squabble over hoplite combat, seeing challenges such as those by Van Wees as unfounded. But somewhere along the way I realized that the mechanics they propose for hoplites pushing each other are simplistic. They are based on an extrapolation of what would work best for two individuals colliding and do not produce the maximum force when men push in ranks. From that realization spawned all of the information on my blog. I have attempted to show the most efficient manner of pushing in mass- if hoplites pushed during battle. I write that disclaimer because some level of pushing is my base assumption, and in earlier posts I have shown the features of the aspis that support this notion. If they never pushed in files, then all of this is irrelevant.

The end product of my research is that I can reconcile the two divergent views on hoplite combat. Hanson was not wrong in principle, just unclear on the mechanics. I don’t fault him for it, that knowledge was beyond his expertise, but his presentation was vulnerable to those who wrote against pushing because I believe many intuitively knew something did not work, and some evidence, like spear fighting before pushing, could not be accounted for sufficiently. But for the fact that the “heretics” did not believe in a push by files, they had many features correct. In a sense it is like the heretics had much of the early phase of battle correct, while the orthodoxy understood the end of battle- or at least of many battles.

Obviously there are not all that many of us interested in hoplites, but I would love to see more people with divergent training put that knowledge to use in the study of hoplites.

By the way, Self-Organization has caught the interest of modern armies. Google it and you’ll find many resources. If you do a Google scholar search on me (Bardunias), you’ll see what I normally publish about insects and how they work in groups.

"Reinstating the Hoplite": Adam Schwartz and the failure of the orthodox view of othismos

A few months back, I promised a review of Adam Schwartz's "Reinstating the Hoplite: Arms, Armour and Phalanx Fighting in Archaic and Classical Greece". In this post I am going to specifically address Section 3.4, Othismos. I’ll restate that this book is a remarkable resource. If you own only one book on hoplite combat, own this one. Much of the book is a filtering and restatement of arguments put forth in a series of papers that make up the great “Heresy-v-Orthodoxy” debate, meticulously footnoted. If you have read all of these papers, then much of this book will not seem novel, but it is nice to have all of this in one place and Schwartz’s commentary is often quite insightful.  His description of othismos is a weakness of the book.


This section begins with a description of othismos as “a common effort, ostensibly by a common push…of the entire phalanx…into the enemy in order to drive them back”, following Hanson’s usage. I agree with this definition and we will need to keep it in mind as we go forward, for Schwartz deviates from it in important ways in his presentation. Following the prevailing notion, which you now know to be incorrect if you have been reading my previous posts, he goes on to describe men hoplites in othismos:

The hoplites in the front stemmed their left shoulder against their shield and thrust it against the shields and bodies of the enemy with all their might; and the ranks behind them in turn stemmed their shields against the backs and right side of the man in front in a ¾ stance, as it were.

In this way, a tremendous pressure could be generated and conveyed through the entire phalanx from the rearmost rank, its force increasing on the way.

 Right away, Schwartz has unwittingly presented us in these two sentences with contradictory mechanics. This is the most glaring problem with the current portrayal of othismos, and the focus of my campaign to correct our understanding. You cannot both stand at a “¾ stance” and sustain “tremendous pressure”. A ¾ stance is one in which your body is held at a diagonal behind the shield, which is facing flush to your foes. The arm is bent, with the arm and body forming an acute angle. This is the natural stance for just about all combat sports, from Asian martial arts to renaissance fencing. Hoplites probably stood this way when engaged in spear fencing. I will do a full post on stances and weapons grips used in hoplite combat at a later date, but for now it is important to understand that in this pose, the only thing holding the shield away from the front of your body is the strength of your arm and shoulder. Were I to grab you by the right shoulder with one hand and the shield with the other and try to force your shield to touch your chest, it is easy to see that very little of your musculature resists my pushing.

Now, even the biggest weight lifter cannot resist “tremendous pressure” with the strength of his arm and shoulder alone. Remember that less than 10 men can generate 1,000 lbs of force or more. So if we take the description of men at ¾ and apply anything approaching the force that can be generated by files of hoplites, the end result will be that the hoplites collapse into the bowl of their shields, chest to underside of the shield rim. Once they collapse into the shield in this way, they occupy less space than they did in the ¾ stance. Thus, as the file closes in there is no room to move back into ¾ stance again unless the files spreads out.

This is important because the current orthodoxy posits a stance with the left shoulder inside the bowl of the shield, pushing on the inner shield-face. Many have interpreted Arrian, the Roman tactician, describing this in a section of his Tactica (16.13). Arrian of course was not a hoplite and the passage in question does not exist in earlier sources for his tactia. He did on the other hand live at a time when Romans formed shield-walls, later called a fulcum, wherein men with very different, single gripped, shields may well have pushed standing sideways at far lower pressure than a hoplite with an aspis could survive.

If we toss out the ¾ stance when pushing, then we can also eliminate the notion that the depth of the aspis was to allow the shield to be rested on the shoulder while pushing. I won’t go on here, but look back to my previous posts to learn how hoplites stood with their shields and a further examination of why the “shoulder rest” function was a side benefit and not the purpose for the depth.

At 3.4.2, the book moves on to describe arguments for and against a literal othismos defined as above. This section is a good distillation of the various viewpoints, but in rebutting the opinions against othismos, Schwartz goes awry. He specifically addresses two arguments: 1) the tremendous force generated by deep files of men would cause a squeeze that would be “distressing to contemplate” in Fraser’s words (1942), and 2) the great pressure would impede weapons usage.

Schwartz is failed here by his reliance on Franz (2002). I must be clear that Franz wrote in German, a language I do not read, so I am only commenting on Schwartz’s translated quotations from that work. With that in mind, what is attributed to Franz shows a lack of understanding of how force is generated in groups of pushing men. He is quoted as writing:

The mass pressure was not achieved by the weight of the warriors, but by their muscles…the mass of the hoplites played a relatively minor role. It came into play chiefly when brief, thrusting impulses were transmitted from one warrior to another.

Schwartz focuses on this and tells us that it “corrects a common enough oversight in the othismos debate.” In fact, Franz, via Schwartz, is propagating a misunderstanding of crowd forces while at the same time being represented as an authority on the subject. Mass is the most important factor in transmitting forces through dense crowds. It is through “leaning” and resting your weight on the man in front, more than “pushing with the legs” that force adds cumulatively in crowds. Members of crowds stand for the most part upright and lean into each other with the upper body angled to some degree. The amount of pressure that can be generated in pushing with the legs is restricted by the angle the legs make with the ground- the closer to perpendicular the less pressure you can generate, with an optimal angle at something acute like 45 degrees depending on how well your feet grip the substrate.

This is important because, as we have seen in crowd data that I presented previously, high pressures within crowds can be maintained for long periods of time. It is in fact the duration of pressure even more than the sheer amount that causes asphyxia in crowds. So, contra Schwartz, the pressure in ranks of hoplites would be “impossible to resisist” without an aspis to protect the diaphragm. His mention of armor as protection against asphyxia, even if true (some reenactors of ECW push of pike battles tell me that the breast and back does help) becomes problematic when we consider the rise in the era of deepest ranks of the organic corslet, sometimes called “tube and yoke” or linothorax.

Schwartz further quotes Franz about what occurs in crowds:

When people behind sense that the pushing does not bring about any immediate advantage, they stop pushing. The result is a kind of reverse thrust.

This statement shows a fundamental difference in a “crowd” of pedestrians and a “crowd” of hoplites in othismos. The hoplites want to generate lethal levels of forces, while crowds do so only accidentally. If we start from the definition of othismos presented at the beginning of this post, then the goal of opposing ranks is to produce the maximum pushing force that they can. What he describes is true for pedestrian crowds, and this behavior is also why we don’t see othismos in every other battle-line in history. Once the front of the file gets squeezed to their limit, they push back on their own men, causing the file to open. In hoplites this did not happen until the pressure became enormous because of their ability to withstand being squeezed without suffocating.

An analogy to what happens between men in Franz’s depiction would be you walking down a hall and pushing against a closed door. If the door does not open, you stop pushing, the feedback telling you it is locked. But if you know the door is locked and your goal is to break down the door, then you do not stop pushing even when the same exact feedback tells you it is locked. You push harder in order to bust it opened. This is what hoplites did. Their “crowds” were meant to push against resistance and overcome it.

Schwartz touches upon this in mentioning crowd disasters, but does not connect the crowd of hoplites to the type of crowd that ends in deaths from asphyxia because he cannot describe why hoplites could survive this. My own examination of the aspis’s role in protecting against crushing of the diaphragm can. There is no reason to expect a group of motivated pushing hoplites to be “like any other crowd moving in a particular direction.”  They are intentionally attempting to generate the maximum sustained force against their opponents, and could generate sustainable forces far in excess of those which occur accidentally in crowds of similar size.

A bit further on, he discusses that othismos could not last long. This has been an objection of many: “How can you push for an extended period?” The answer again comes from an understanding of crowds. Pressure can be maintained within crowds at rock concerts for long periods.  Force will vary over time, but not in the quick oscillations Schwartz envisions.  There could be "lulls", the force reducing as men simply unpack to catch their breath, perhaps even pulling completely apart and engaging at spear range again.

At the end of this section, following the prevalent notion of hoplites charging directly into othismos, he brings up the fact that many units charge, even when occupying positions of superior height. He portrays them as abandoning tactical advantage for momentum. I won’t dwell on this, but Polybios specifically describes the problem with not charging downhill during the battle of Sellasia (2.68), and it has nothing to do with momentum for othismos.

The second objection he addresses is that weapons cannot be used in othismos. He quotes Cawkwell’s statement that men would “better be able to use their teeth than their weapons”. I’ve addressed this at length, and I was glad to see that Schwartz also saw the utility of the short sword in the press of othismos. He correctly sees the limitations of the spear in othismos and presents the overhand grip as the exclusive strike for use within the phalanx as well. I’ll delve into that deeper in a future post.

He also does a great job of showing the folly of van Wees’s notion that the aspis cannot be used to push because it was held up at a slant and only the bottom rims would collide. Obviously, the men would simply collapse into their shields as they push and Schwartz points this out. Unfortunately, he did not see that this same logic applies to men standing at ¾ stances as I described above.

He also twists Xenophon (Cyr. 7.1.33) to mean that the aspis was rested on, not against, the shoulder. The clear reading of the passage is that the shield was rested against the shoulder/upper arm, and this can certainly be read as a description of the way I portray hoplites as resting the rim against the front of the shoulder, on the broad shoulder piece of the organic corslet. Note that some depictions show these stiff shoulder pieces extending wider than the shoulder, so if you push with the shield on the shoulder the stiff pad gets jammed into your neck!

Section 3.4.3 is an examination of the morale effects of added ranks, which are in no way incompatible with othismos, but works alongside it. In 3.4.4, he discusses the need to maintain cohesion. Goldsworthy’s notion of depth as a means of maintaining cohesion in the presence of broken terrain is mentioned, but as I have shown previously, there is no record of 25 or 50 rank phalanxes deploying from this depth into a shallower, broader line. Unless these men are meant to stand idle until the front ranks somehow break through, getting more men into the area is not helpful unless they can move to a shallower formation and engage the enemy.

He describes the Argive predilection to run too early into the charge and notes that this tore holes in the formation between them an adjacent units. Interestingly, he goes on to describe Spartans foregoing the charge, but does not seem to realize that this too must result in gaps between them and adjacent units that did have a running charge. The whole line cannot have arrived simultaneously against the enemy line if part walked and part ran. This has been overlooked by everyone to my knowledge.

Following the common model of othismos, he mentions hoplites charging 50 m (later 20-25m) in order to impart “a maximum of penetration power at the collision”. The real cause of the charge has more to do with the “tremendous nervous pressure” he also describes, because it takes only a few yards to achieve the “ramming speed” suggested by the orthodoxy. Any distance in excess of that simply causes fatigue and a loss of cohesion for no gain of momentum. In fact, the whole notion of a charge like an un-horsed medieval knight imparting maximum pressure is a fallacy, as I have previously demonstrated. Dense packing is far more important for a strong and sustainable force even if it occurs at slow speed.

It is in the final section, 3.4.5, that Schwartz’s portrait of othismos falls apart. He again draws on “observations of crowd behavior” to portray othismos as a “phenomenon occurring at intervals”. He applies what I is think a wildly inappropriate reference on Spartan leaders having trouble keeping the rear ranks from pushing forward to initiate the charge to show that rear ranks could push forward when locked in combat. I do believe that they did push forward within the file, but this reference cannot be applied. Cavalry were famous for “chomping at the bit” to rush into the charge as well, but there is not corresponding push when engaged in combat.  Using an innapropriate reference gives ammo to the foes of othismos.

Inexplicably, he abandons the ¾ stance, where men push their shields into the back of those in front, for Luginbill’s “T” shaped, side-on stance where men push into the side and right shoulder of those in front. Then he has the file leaders being propelled into the enemy ranks by the file behind them “killing left and right”. Far more likely is getting “killed from left and right”. More importantly, the overlapping of shields within each succesive rank make any single file pushing through the stacked ranks and out of formation, then into the enemy’s overlapped ranks, unlikely.

He states that: “Such othismos may have occurred in short bursts, and at random intervals, as the rear ranks felt they might help their comrades by applying pressure. And not all 7 ranks need to participate in shoving simultaneously…” This is a radical departure from Hanson's “a common effort, ostensibly by a common push…of the entire phalanx…into the enemy in order to drive them back”. In fact, what he goes on to describe is nothing unique to hoplites. Romans and pretty much any linear formation in ranks surely had disorganized pushing by eager men behind the front ranks. This interpretation makes “othismos” so common in the history of warfare that it hardly warrants a special term in the Greek context. This commonality also goes a long way towards unraveling all of the arguments for the form of the panoply being derived from the need to be effective in the “push”. Any Roman with a scutum could do what Schwartz advocates and frequently did.

Part of the problem is that Schwartz is in a bit over his head. I do not say this disparagingly. I applaud him for attempting to bring in concepts from crowd mechanics even if he ultimately does not sufficiently understand them. A statement that hoplite battles were “essentially chaotic” is ironic, because I agree with him, but my understanding of chaos is clearly far different from his own. The phrase “no one to direct the movements of the enormous organism” is so close to what I believe the truth, but we need to add an understanding of how order emerges from seemingly ‘chaotic’ interactions within groups. The study of how this occurs through what is called self-organization will ultimately yield a clearer understanding of hoplite combat. Groups of men, like flocks of birds or schools of fish, can achieve a great degree of cohesion and coordination through simple interactions between men in a bottom-up fashion, and do not require the top-down direction of generals for much of what occurs in combat. Thus, we do not need “a referee with a whistle” as Holladay (1982) said would be needed to move from one phase to another. Such “phase transitions” can arise simply from the interactions of individual hoplites in the absence of specific orders.

Three Myths of Othismos

As you can tell by now, I am an advocate of a literal pushing othismos. Because of this I am frustrated by some elements of the pro-othismos arguement as it is currently put forth. I've mentioned these problems previously, but they bear repeating:

Myth 1: "The rim on the aspis evolved as the shield became heavier to allow the weight to be borne on the shoulder as well as the arm."

If you look at the cross-section of an aspis, it is clear that the rim section is far thicker than the core of the face of the shield. Thus a substantial portion of the weight of the shield is in the very rim that they would hypothesize grew to ease the carrying of said weight! A rimless aspis is no heavier than many other single grip shields. Sure, there are images that show the hoplites hanging the shield of their shoulder by the rim, but there are far more showing hoplites with their Corinthian helms pushed back, and I doubt many would support fighting with them in this position. Hanging the aspis by its rim on the shoulder simply takes advantage of the profile, which evolved for a very different purpose.

Myth 2: "Hoplites pushed en masse with their bodies side-on, their left shoulders in the bowl of the aspis, pressing into the back of the man in front."

The illogic of this one becomes apparent if we try to envision a file doing so. Clearly this can only work for the second ranker pushing the first ranker. Beyond that the men's backs are perpendicular to the men behind them! The could push into the right shoulder of the men in front, but that renders weapons play impossible- something the side-on stance is supposed to allow. The other problem is that at anything approaching maximum pushing force for a file, the men would collapse into the bowl of their shields in any case and be square to the foes as they should be.

Myth 3: "Hoplites charge rapidly to add momentum to othismos."

This one is counterintuitive, so I don't blame them for not foreseeing it, but a slow packed advance generates more force, faster than a series of single men impacting like rams. With no need to move to othismos directly from the charge, an extended period can occur of spear fencing prior to a pushing occurring. This eliminates a major difference between the pro- and anti- push crowds.

Crowds don't need to be big to generate extreme forces.

One of the most common objections to my model of the othismos phase of hoplite combat as essentially two crowds moving against each other stems from the fact that for most readers the mechanics of crowd pushing is counter-intuitive. They simply do not believe that "crowds" of only a few ranks deep can generate lethal force. To make this clearer I'm posting some snippets from J. Fruin's "The causes and prevention of crowd disasters."

Crowd forces can reach levels that almost impossible to resist or control. Virtually all crowd deaths are due to compressive asphyxia and not the "trampling" reported by the news media. Evidence of bent steel railings after several fatal crowd incidents show that forces of more than 4500 N (1,000 lbs.) occurred. Forces are due to pushing, and the domino effect of people leaning against each other.

So our common notion of "pushing" may not be adequate to completely describe what occurs. The most force may actually be transferred through coordinated "leaning" when crowd densities are very high.

Experiments to determine concentrated forces on guardrails due to leaning and pushing have shown that force of 30% to 75% of participant weight can occur. In a US National Bureau of Standards study of guardrails, three persons exerted a leaning force of 792 N (178 lbs.) and 609 N (137 lbs.) pushing. [9] In a similar Australian Building Technology Centre study, three persons in a combined leaning an pushing posture developed a force of 1370 N (306 lbs.). [10] This study showed that under a simulated "panic", 5 persons were capable of developing a force of 3430 N (766 lbs.).

Only three people exerted a force horizontally against a target by simply leaning into each other that would be the equivalent of the weight of a grown man laying on top of you. Now, you may think that you could bear this weight without suffering from asphyxia, but for how long? If the pressure from even this small group were maintained for any length of time you would succumb to exhaustion and be unable to inflate your lungs. The effect is similar to what occurs when constricting snakes, like pythons and boas, kill. The don't so much crush the breath out of you as simply make it incrementally more difficult for you to expand your diaphragm to take in air.

Another common assumption is that two opposing groups could not generate these forces against each other, that a crowd must be pushing in one direction against a wall. This next quote shows how crowd collisions can be deadly.

In the Cincinnati rock concert incident, a line of bodies was found approximately 9 m (30 ft) from a wall near the entrance. This indicates that crowd pressures probably came from both directions as rear ranks pressed forward and front ranks pushed off the wall.

I hope this demonstrates that phalanxes of 8 ranks could be deadly. Simply scaling up the leaning force from 3 people (178 lbs)to 8 people gives us 475 lbs. There is surely a loss due to lack of coordination, so this figure is probably high, but it shows the principle.

Taking just the conservative leaning estimate, 12 on 12 would be over 720lbs and 16 on 16 ranks might approach 1,000lbs.

Now how exactly to scale up these pressures I do not know, so these are simply ballpark figures. Perhaps they reflect peak pressures, or peak pressures might be much higher. Sustained pressures are smaller, but even a fraction of this force would be deadly unless the hoplites were protected by the aspis. Peak pressures could surely even crush the aspis, as we know occurred in some battles, which would then leave the hoplite defenseless against further compression.

For some further reading: http://www.crowddynamics.com/Main/Fruin%20-%20causes.htm

Crowd othismos model

If you've read the paper below then you already know this, but I will summarize the key points and contrast them with the other two alternative views (simplified of course).

Orthodox view: Othismos is literally a mass pushing match with the aim being to push opponents back until the cohesion of their battle-line breaks. In the most widely proposed form, the clash of hoplite phalanxes progressed along the following pattern: Both phalanxes charged at a slow run from about 200 meters apart. Hoplites move directly into shield-on-shield contact from the charge using the momentum to smash their shields together like rams and stabbing with spears underhand like cavalry lances. Spears are often shivered and opposing ranks become to some extent interlaced. This is followed by intense infighting with swords as ranks reform through a process not well explained and the ranks behind the front-rankers begin to push forward. It is this pushing phase that is labelled “othismos” (pushing) and the pushing is done side-on to the man in front with the left shoulder in the bowl of the shield. This othismos continues until one side gives way and collapses. Once one side collapses the victors pursue (but not too far) and the losers sustain many casualties.

Heretical view: There are many variations of this, so I shall present it as I think most consistent with the hoplite panoply. The progress of battle differs from the orthodoxy in that there is no running charge directly into combat. They note that the run would cause disorder in the ranks that this would be counter to the whole idea of forming ranks in the first place. Combat occurs at spear's length, perhaps with shields overlapped, perhaps not, in a phase known to the Hellenistic Greeks as doratismos. Fighting might then progress to infighting with shield-bashing on an individual, uncoordinated scale. While the front-rankers and the one or two ranks behind them fight, the men to the rear provide only moral support and make ready to step over their corpses to take a place in the battle line. The advance of the phalanx is figuratively labelled “othismos” as we might speak of an armored "push" of tanks and mechanized infantry. Fighting occurs until one side gives way due to mounting casualties and morale failure. As before, the losing side suffers as the victors pursue.

Othismos-crowd model: This view incorporates elements of both of the above. In my view there is a running charge from a couple hundred meters as in the view of the orthodoxy, but with spears held up overhand. This does not lead directly into othismos, for there is no crash of hoplites seeking to use momentum to bash into their foes, and thus no interlacing of opposing ranks. Front ranks pull up from the charge prior to shield contact with their foes, then close to the approximately 5' distance from their foes that reflects the reach of the dory, entering doratismos as in the heretic's view. They then spear fence en masse as envisioned by the heretics, but at a spacing of something less than 1 m frontage, their aspides just overlapped. Only the second rank uses their spears in support of the front rank.
At some point there is a shift in phase to fighting at less than spear range. Closing to less than spear range would be natural if a hoplite’s spear was broken, for he would then find himself with the choice of standing in the ranks unable to reach the enemy, leaving the ranks to move in close, or staying in the ranks, but pressuring the men beside him to move in as a group. As more spears are lost this urging in close magnifies until the line moves. This describes how the move into close range could emerge without any central command, but it is possible that men were purposefully led into close range fighting.
It is possible to move from advance to othismos without a spear-fencing stage, but it is unlikely that this occurred as the more recent formulations of the orthodoxy put forward, with men running into each other in an uncoordinated manner. In order to maximize force, the men must pack their files tight before they hit the enemy phalanx rather than run in directly from the charge. Spartans would have had an easier time of this due to their slower advance.
However it occurs, when the opposing units are in close contact, the rear rankers close up behind those in front for physical support. The weapons used by hoplites are well designed for this type of fighting over the top of the shield rims. The ranks continue to tighten until the men are belly to back with the men in front and behind. How long this takes can vary with training in a polis or over time, but eventually this compact mass enters the othismos phase of battle. If the opposing front rankers are already shield to shield, then the progression to othismos is gradual and fluid. If they are at a distance, then there is a short and shuffling charge by the whole mass (as seen in the videos on this site). The two phalanxes now function like crowds, generating intense force as they push against each other. Men in the middle of the mass do not control their own movement, but ride the waves of flesh, all the while fighting and defending with sword or broken spear in their upraised right arm. The pressure is enough that these men would be asphyxiated without the aspis. If shields break under the pressure men die, unless they can breathe within the bowl of the overlap of the man to their right's shield. There may be lulls in the combat where the opposing phalanxes loosen this tight level of packing due to exhaustion, the front men may still be fighting or they too may pull apart. Eventually one side gives way and the same pursuit seen in the other models occurs.

As you see, my model incorporates the possibility of extended initial doratismos with literal othismos. My othismos is a far more brutal thing than that described by the orthodoxy. The momentum of men charging at 5 mph produced forces that are similar to the maximum seen in the crowd-crush. More importantly, individual collisions are also instantaneous, lasting a few miliseconds, while the pressure within crowds can be maintained for extended periods and is far more lethal. Men pushing side-on with the shoulder in the shield cannot generate the enormous crowd-like crushing forces that men pushing belly to back can. As the pressure builds, side-on men will collapse to belly to back if there is room to, and if there is no space between them and the men beside them, then they are vulnerable to asphyxia since their diaphragm is not in the belly of the shield.


To a buzzard circling the battlefield othismos would look like this, with only the rear rankers able to push sideways.



If we compare a side-on to belly to back postures of hoplites n the phalanx, you will see the difference in the density of the crowd packing, though the side-on man have a more narrow frontage. Under pressure these sideways men will collapse to face forward, absorbing the force of the men pushing them from behind instead of transferring it to the man in front of them. The pushing forces generated by a crowd can be greater than the smashing force of an initial running collision of shields, and there is no disruption of order from interlacing front ranks.



As I am able I will add more comparative details of the mechanics. So far I have not leaned heavily on primary sources, but I am putting together a post in which I shall interpret the words of ancient authors to support my position, just as both the heretics and orthodoxy have used alternate interpretations of many of the same quotes to support their position and rule out the other.