Xerxes (c. 529-465 BC). King of Persia. He succeeded his father Darius in 486 BC and in 480 invaded Greece with enormous forces. After meeting unexpected resistance at Thermopylae, he was defeated by sea at Salamis (480) and by land at Plataea (479). Xerxes continued his father’s massive building project at Persepolis. A harsh ruler, he was assassinated in a palace intrigue.