Ajax is a Greek mythological hero, the son of King Telamon and Periboea, and the half-brother of Teucer. He plays an important role, and is portrayed as a towering figure and a warrior of great courage in Homer's Iliad and in the Epic Cycle, a series of epic poems about the Trojan War. He is also referred to as "Telamonian Ajax" (Αἴας Τελαμώνιος, in Etruscan recorded as Aivas Tlamunus), "Greater Ajax", or "Ajax the Great", which distinguishes him from Ajax, son of Oileus (Ajax the Lesser).

In Homer's Iliad he is described as of great stature, colossal frame and strongest of all the Achaeans (The Achaeans constitute one of the collective names for the Greeks in Homer's Iliad). Known as the "bulwark of the Achaeans", he was trained by the centaur Chiron (who had trained Ajax's father Telamon and Achilles's father Peleus and would later die of an accidental wound inflicted by Heracles, whom he was at the time training), at the same time as Achilles. He was described as fearless, strong and powerful but also with a very high level of combat intelligence. Ajax commands his army wielding a huge shield made of seven cow-hides with a layer of bronze.

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