The famous battle fought at Thermopylae in 480 BC was a pivotal encounter during the Greco-Persian Wars between an alliance of Greek city-states and the invading Persian forces led by King Xerxes I. The most notable aspect of this battle was the leadership of King Leonidas I of Sparta, who, along with a small contingent of about 300 Spartans and other Greek allies, held off a vastly larger Persian army for three days. The stand at Thermopylae became a symbol of bravery and sacrifice against overwhelming odds. Although the Greeks were ultimately defeated, their resistance delayed the Persian advance and inspired further Greek successes.