Born 508 or 507 B.C. in Sparta; died 480 B.C. at Thermopylae. King of Sparta from 488 to 480 B.C. (ancient Greece).
In the period of the Greco-Persian wars, Leonidas headed the allied force of the Greek poleis against the Persian king Xerxes in 480, when the Persians invaded Greece. He died in the Battle of Thermopylae, covering with a small detachment the retreat of the main part of the Greek Army. In ancient tradition the name of Leonidas is a symbol of patriotism and military valor.