Definition
Xerxes the Great, or Xerxes I, was a powerful ruler of the Achaemenid Empire (ancient Persia) in the 5th century BC. He is most famous for his massive military campaign against Greece, including the battles of Thermopylae and Salamis. Xerxes aimed to expand the Persian Empire's influence and control over the Greek city-states. His reign represents both the peak and the beginning of the decline of Persian power. He's remembered for his ambition and vast military resources.