Clearchus

Greek military officer

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June 17, 2026

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Clearchus was a 5th-century BC Greek soldier and governor of Byzantium. He is known for his role as a mercenary commander under Cyrus the Younger at the Battle of Cunaxa in 401 BC. In this battle, Clearchus led nearly 13,000 Greek mercenaries, who were the best-trained troops in Cyrus's army. They successfully routed the Persian left flank. Despite this success, Cyrus was killed in the battle, and his forces were defeated. Clearchus then led the famous "Retreat of the Ten Thousand" under Xenophon, guiding his troops through hostile territory to the Black Sea.12

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Battle of Cunaxa
Greek mercenaries under Clearchus, nearly 13,000 strong and the best trained and equipped troops in Cyrus’ army, routed the Persian left with few casualties, while Cyrus himself charged Artaxerxes’ centre with 600 cavalry. Cyrus succeeded in wounding his brother but was killed. When the Greeks returned, they found…
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Greek mercenaries under Clearchus, nearly 13,000 strong and the best trained and equipped troops in Cyrus’ army, routed the Persian left with few casualties, while Cyrus himself charged Artaxerxes’ centre with 600 cavalry. Cyrus succeeded in wounding his brother but was killed. When the Greeks returned, they found…
Read More