Principes

Principes (Singular: princeps) were spearmen, and later swordsmen, in the armies of the early Roman Republic. They were men in the prime of their lives who were fairly wealthy, and could afford decent equipment. They were the heavier infantry of the legion who carried large shields and wore good quality armour.

Their usual position was the second battle line. They fought in a quincunx formation, supported by light troops. They were eventually disbanded with after the Marian reforms of 107 BC.

According to Pat Southern, principes appear to have been born from remnants of the old second class of the army under the Etruscan kings when it was reformed by Marcus Furius Camillus. The second class stood in some of the first few ranks of a very large phalanx and were equipped in a similar manner to principes. They would support the heavier first class in the front ranks. It is probable that engagements with the Samnites and a crushing defeat at the hands of the Gallic warlord Brennus, who both used lots of smaller military units rather than a few very large ones, taught the Romans the importance of flexibility and the inadequacy of the phalanx on the rough, hilly ground of central Italy.

In the early Camillan system of organisation of the 3rd and 4th centuries BC, men were sorted into classes based on wealth, the principes being the wealthiest after the triarii.Principes were armed with short spears, or hastae, up to 1.8 metres (6 ft) long. They fought in a quincunx formation, usually carrying scuta, large rectangular shields, and bronze helmets, often with a number of feathers fixed onto the top to increase stature. They wore heavier armour types, the most common form being chainmail, which offered a good degree of protection without hindering movement.

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