Leonidas, “son of the lion” died 480 BC also known as Leonidas the Brave was a Greek hero-king of Sparta, the 17th of the Agiad line, third son of Anaxandridas II of Sparta, who was believed to be a descendant of Heracles, possessing much of the latter`s strength and bravery. He is notable for his leadership at the Battle of Thermopylae was fought between an alliance of Greek city-states, led by King Leonidas of Sparta, and the Persian Empire of Xerxes I over the course of three days, during the second Persian invasion of Greece. It took place simultaneously with the naval battle at Artemisium, in august or September 480 BC, at the narrow coastal pass of Thermopylae (The Hot Gates). The Persian invasion of Greece ended by the Athenian victory at the Battle of Marathon in 490 BC.