Polybius provides a detailed description of Roman Legionary equipment in Book VI of his Histories. He begins by describing infantry equipment and then describes the equipment of the cavalry and auxiliaries in turn. This post will concentrate on his description of the equipment worn by the four classes of citizen infantry velites, hastatii, princeps, and triarii.
The velites were light troops or skirmishers. They were equipped with a plain helmet, sword, javelins, and a shield called a parma. According to Polybius, the shield was round and about 3 Roman feet in diameter. The javelins were also 3 Roman feet long and had an iron point made such that it was supposed to bend on impact and be useless to the enemy. From the description, it sounds like the pilum, or at least a precursor to it. Oftentimes, the velites would cover their helmets with animal skins to distinguish themselves in battle.
The hastatii, princeps, and triarii were all heavy infantry and were equipped completely differently from the velites. The hastatii and princeps were armed with a shield, helmet, sword, spears. The helmet was similar to that worn by the velites with the exception that it had a crest of two or three red or black feathers. The sword was a short, “Iberian†sword as Polybius calls it that had two sharpened edges and a sharpened point; this allowed the sword to be used for slashing and stabbing in close combat. Again, from the description, this sounds like the famous Roman gladius somewhat similar to the one used by Russell Crowe in the film Gladiator. The shield was rectangular with curved surface about 2 ½ feet wide by four tall. It was made of two layers of wood covered with skin and with an iron edge to further protect it against oblique sword strikes. The spear was made for throwing and was approximately 8 feet long with the bottom half of the shaft made of wood and the top half made of iron with a sharpened point.
The triarii were armed the same as the hastatii and princeps with the exception that their spear was a more traditional long spear with a long wood shaft and a shorter head. Lastly, all three classes of heavy infantry wore a square plate of armor on their chest called a “heat-guard†while the wealthy troops forsake this in favor of a corselet of chain mail.
All the equipment of the legion was specialized for infantry combat. The velites softened up the enemy before the hastatii, princeps, and triarii closed in to complete the destruction of their enemies in close melee combat.