The Art of War
The Quincux Formation
Above a flash animation of this Roman tactical
Formation
The Quincux or checkerboard formation
Following Livy and Polybius, many authors describe a legion formation with gaps between the maniples or cohorts equal to the width of the unit itself so the units of the second line could advance through the gaps while the first line retreated. The flash movie above demonstrates how this could have worked. First the hastati would engage the enemy, after the velites harassed the enemy for a while. When the hastati got tired, the principes would change position with the hastati. if the hastati also would not be victorious, the triarii would eventually make a "last stand".
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Triarii*) |
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Principes*) |
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Hastati*) |
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Velites*) |
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Enemy*) Phalanx |
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Enemy*) Celts |
*) The models used for this movie are actual pictures of my Roman republican army...
The history of Rome, by Livy
... When the battle formation of the army was completed, the hastati were the first to engage. If they failed to repulse the enemy, they slowly retired through the intervals between the companies of the principes who then took up the fight, the hastati following in their rear. The triarii, meantime, were resting on one knee under their standards, their shields over their shoulders and their spears planted on the ground with the points upwards, giving them the appearance of a bristling palisade. If the principes were also unsuccessful, they slowly retired to the triarii, which has given rise to the proverbial saying, when people are in great difficulty "matters have come down to the triarii." When the triarii had admitted the hastati and principes through the intervals separating their companies they rose from their kneeling posture and instantly closing their companies up they blocked all passage through them and in one compact mass fell on the enemy as the last hope of the army. The enemy who had followed up the others as though they had defeated them, saw with dread a now and larger army rising apparently out of the earth ...
The histories of Polybius, by Polybius
... Scipio drew up his army in the following fashion. In front he placed the hastati with certain intervals between the maniples and behind them the principes, not placing their maniples, as is the usual Roman custom, opposite to the intervals separating those of the first line, but directly behind these latter at a certain distance owing to the large number of the enemy's elephants. Last of all he placed the triarii. The intervals of the first maniples he filled up with the cohorts of velites, ordering them to open the action, and if they were forced back by the charge of the elephants to retire, those who had time to do so by the straight passages as far as the rear of the whole army, and those who were overtaken to right or left along the intervals between the lines ...
The problem
The formation presents a problem. Many argue that the legion could not have gone into battle with such large gaps because the enemy would have used them to penetrate the Roman position. Against phalanx formations this tactic could work, but against (Celtic) war bands this tactic would certainly be a disaster; the Celts would pour into the gaps and attack the manipul that stayed in the flank, and would make if almost impossible for the retreating manipul to retreat in order.
In the flash movie at the top of this page I deliberately did not let the phalanx move up. Down here you can see the Celts breaking through.
Above a flash animation of how things might go
wrong
