§ 1. Crassus formed a square against the Parthians, so that twelve cohorts held each side and a troop of cavalry was attached to each cohort. But he did this in alarm and like a man stunned. For by dividing the cavalry he rendered every part weak, although the Parthians were superior in cavalry.
§ 2. The Triballi in Stobaeus, Discourse 52, make a different disposition. The first part contains the weak, who provoke the enemy to battle; the second, the strongest; the third, cavalrymen; the fourth, women.
Xanthippus’s battle-line was skillfully contrived. For he commanded the light-armed auxiliaries to provoke the enemy and withdraw; the bravest men then received the enemy, and while the battle took place between them, the auxiliaries were again to break out from the wings.
Cyrus, following Croesus’s counsel, advanced into the kingdom of Tomyris, whereas otherwise he would have lost his kingdom. Herodotus, book 1. And there he established a new battle-line by which he also conquered.
§ 3. Those who have chariots and elephants place them in the first battle-line. For they very easily throw the enemy’s ranks into disorder, whereas if they are in the middle of the battle-line they crush whatever stands in their way.
§ 4. The battle-line of the Hungarians against the Turks, established by Toroneus, had cavalrymen and infantrymen intermingled, so that it could not be surrounded; for he expanded the ranks in such a way that it was equal to a great multitude.
They now approve another method, which is customary. Against the Turks’ crescent-shaped battle-line the army must be divided into three parts, so that two fight against the wings while the middle battle-line remains immovable until it comes together with the enemy and fights.
§ 5. Alexander also established another battle-line at Arbela. Frontinus, book 2, chapter 3: “When Alexander at Arbela feared the multitude of the enemy but trusted the valor of his own men, he formed a battle-line facing in every direction, so that, if surrounded, they could fight on every side.”
§ 6. Vegetius proposes several kinds in book 3, chapter 20:
“There are seven kinds or manners of fighting when hostile standards clash on each side. The first manner of fighting is with a long front and a squared army, just as battle is customarily conducted even now and almost always. But men skilled in arms do not judge this manner of fighting to be the best, because when the battle-line is extended over a long space, the ground that occurs is not always level; and when a hollow or curve occurs in some part of it, the battle-line is frequently broken in that place. Moreover, if the adversary is superior in number, he surrounds either the right or the left wing from the flanks. In this lies great danger unless you have surplus troops to run forward and sustain the enemy. Only the man who has both more numerous and brave warriors ought to engage by this method, so that he may surround the enemy from each wing and enclose the hostile army, as it were, within his own bosom.
“The second manner of fighting is oblique, and is much better. In it, if you arrange a few vigorous men in a suitable place, even if you are troubled by the enemy’s multitude and valor, you will nevertheless be able to carry off victory. Its method is as follows. When the formed battle-lines come to the encounter, you will then separate your left wing farther from the enemy’s right, so that neither missiles nor arrows reach it. But join your right wing to his left wing, and there first begin the battle, so that with your best cavalrymen and most approved infantrymen you attack and encircle his left part, to which you have joined yourself, and, by thrusting it back and overrunning it, reach the enemy’s rear. If you once begin to drive the adversaries from there, as your own men come up you will attain an undoubted victory, while the part of your army which you have removed from the enemy will remain secure. In this manner of fighting the battle-line is formed in the likeness of the letter A or a carpenter’s level. But if the adversary has done this first, you will gather at your left wing those cavalrymen as well as infantrymen whom we have said ought to be placed as surplus troops behind the battle-line, and thus you will resist the adversary with great forces, lest you be driven away by his art.
“The third manner of fighting is similar to the second, but is worse in this respect: you begin from your left wing to clash with his right. For the assault of those who fight on the left wing is, as it were, maimed, and men whose bodies are exposed attack the enemy with difficulty. I shall explain this more clearly. If at any time your left wing is much better, join the strongest cavalrymen and infantrymen with it, and in the encounter apply it first to the enemy’s right wing; and hasten as much as you can to drive back and surround the adversary’s right part. But remove the other part of your army, in which you know that you have the worse warriors, as far as possible from his left, lest it either be attacked with swords or reached by missiles. In this kind care must be taken lest your battle-line be struck transversely by the enemy’s wedges. Battle will be conducted advantageously in this manner in one case only: if the adversary has a weaker right wing and you a much stronger left.
“The fourth manner of fighting is as follows. When you have formed the battle-line, four or five hundred paces before you reach the enemy, who does not expect it, you ought suddenly to urge forward both your wings, so that from each wing you may unexpectedly turn the enemy to flight and attain victory more quickly. But although this manner of contest swiftly conquers if it brings forward trained and exceedingly brave men, it is nevertheless dangerous, because the man who fights thus is compelled to expose his middle battle-line and separate his army into two parts. If the enemy is not conquered at the first assault, he afterward has an opportunity to attack both the divided wings and the abandoned middle battle-line.
“The fifth manner of fighting is similar to the fourth but has this one thing in addition: it places light-armed troops and archers before the middle battle-line so that, by resisting, they may prevent it from being broken into. For thus it attacks the enemy’s left with its own right wing and the enemy’s right with its own left. If it can put the enemy to flight, it immediately conquers; if not, its middle battle-line does not suffer because it is defended by the light-armed troops and archers.
“The sixth manner of fighting is the best and almost similar to the second. It is employed by those who despair of both the number and valor of their own men, and, if they have formed their line well, they often attain victory although they have fewer men. For when your formed battle-line approaches the enemy, join your right wing to the enemy’s left and there begin the battle by means of the most approved cavalrymen and the swiftest infantrymen. But remove the remaining part of your army as far as possible from the adversaries’ right part and extend it in a straight line like a spit. For when you begin to cut down their left part both from the flanks and from the rear, you will without doubt turn them to flight. But the adversary cannot assist his struggling men either from his right part or from the middle battle-line, because your battle-line is extended and stretches in its entirety in the likeness of the letter I, and withdraws very far from the enemy. Battle is often joined by this method on marches.
“The seventh manner of fighting is one in which the advantage of the place assists the combatant. In this manner also you will be able to withstand the adversary both with fewer and with less brave men. That is, if on one side you have a mountain, sea, river, lake, city, marshes, or precipices from which the enemy cannot approach, and arrange the rest of your army in a straight battle-line. But on the wing which does not have a fortification you should place all the cavalrymen and ferentarii. Then you will fight more securely with the enemy at your discretion, because on one side the nature of the place fortifies you, while on the other almost double cavalry is placed.
“Nevertheless, this must be observed, for nothing better is found: whether you wish to fight with the right wing alone, place the bravest men there; or with the left, station the most vigorous there; or if you wish to form wedges in the middle by which you may break the enemy’s battle-line, arrange the most experienced warriors in the wedge. For victory is customarily achieved by a few. It is enough that men selected by the wisest commander be arranged in those places which strategy and advantage require.”
§ 7. The battle-lines of Archelaus and Sulla departed greatly from the common formation. Frontinus, book 2, chapter 3:
“Against Lucius Sulla, Archelaus placed scythed chariots in front to throw the enemy into disorder; in the second battle-line, the Macedonian phalanx; in the third, armed auxiliaries according to the Roman custom, intermingled with deserters of the Italian nation, in whose agility he had the greatest trust; and he stationed the light-armed troops in the last position. Then on each flank he placed cavalry, of which he had a great number, for the purpose of surrounding the enemy.
“Against these measures Sulla drew trenches of great breadth on each flank and fortified their ends with forts. By this method he secured himself from being surrounded by an enemy superior in the number of infantry and especially in cavalry. Then he formed a triple battle-line of infantry, leaving intervals through which he might send the light-armed troops and the cavalry, which he had stationed in the last position, when circumstances demanded it. He then commanded the soldiers before the standards, who were in the second battle-line, to drive thick, numerous stakes firmly into the ground. As the chariots approached, he withdrew his battle-line within the stakes and behind the standards. Then at last, after a universal shout had been raised, he ordered the velites and light-armed troops to shower missiles upon them.
“When these things had been done, the enemy’s chariots either became entangled in the stakes or, terrified by the shouting and missiles, turned against their own men and threw the Macedonian formation into disorder. When it gave ground while Sulla stood firm, and Archelaus opposed his cavalry, the Roman cavalrymen, suddenly sent forward, turned them away and completed the victory.”