Answer
Cyrus the Younger, a Persian prince, employed Xenophon as a mercenary general in his military campaigns. Xenophon, a Greek historian and military leader, played a crucial role in Cyrus's attempt to seize the Persian throne from his older brother, Artaxerxes II. Xenophon's military expertise and leadership were instrumental in Cyrus's initial victories, but the campaign ultimately failed, and Cyrus was killed in battle.