Surnamed the Great, or the Elder, the founder of the Persian empire; began his conquests by overthrowing his grandfather Astyages, king of the Medes; subdued Croesus, king of Lydia; laid siege to Babylon and took it, and finished by being master of all Western Asia; was a prince of great energy and generosity, and left the nations he subjected and rendered tributary free in the observances of their religions and the maintenance of their institutions; this is the story of the historians, but it has since been considerably modified by study of the ancient monuments (560-529 B.C.).