The artistic convention of heroic nudity was established in the art of ancient Greece by the Archaic period.
Polybius' Histories describe how the Gaesatae, hired by other Celtic peoples, the Boii and Insubres, as mercenaries to fight the Romans, stood naked at the head of their army at the Battle of Telamon in 225BC.
[2] Diodorus Siculus reported other instances of such combat: "Some use iron breast-plates in battle, while others fight naked, trusting only in the protection which nature gives.
"[3] Livy tells of how the Tolistobogii of Galatia fought naked, being proud of their spilt blood and even widening gashes they received themselves.
Polybius describes them as fighting naked, armed only with their oval shields and long swords, although Livy has them only nude from waist up.