Ab urbe condita

The phalanx formation, similar to the Macedonian of the earlier days, was abandoned in favour of the distribution into companies (manipuli); the rear portion being broken up into smaller divisions.

The foremost line consisted of the hastati, formed into fifteen companies, drawn up at a short distance from each other.

These were called the lightarmed companies, as whilst one-third carried a long spear (hasta and short iron javelins, the remainder carried shields. This front line consisted of youths in the first bloom of manhood just old enough for service.

Behind them were stationed an equal number of companies, called principes, made up of men in the full vigour of life, all carrying shields and furnished with superior weapons. This body of thirty companies were called the antepilani.

Behind them were the standards under which were stationed fifteen companies, which were divided into three sections called vexillae, the first section in each was called the pilus, and they consisted of 180 men to every standard (vexillum). The first vexillum was followed by the triarii, veterans of proved courage; the second by the rorarii, or “skirmishers,” younger men and less distinguished; the third by the accensi, who were least to be depended upon, and were therefore placed in the rearmost line.

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.”