Sophaenetus of Stymphalus was a Greek military commander and historian from Arcadia active in the late 5th and early 4th centuries BCE. His historical importance derives from his participation as a senior general in Cyrus the Younger’s expedition against Artaxerxes II in 401 BCE.

After Cyrus’s death and the seizure of the Greek commanders, Sophaenetus survived and advocated for appointing new leaders to guide the retreat of the Ten Thousand. No further biographical details are recorded.

He is credited with writing an Anabasis of Cyrus, a lost historical work presumably covering the same events as Xenophon’s Anabasis. Its existence is noted only in the 10th-century Byzantine encyclopedia, the Suda.

Sophaenetus is a verified participant in the march of the Ten Thousand, providing a historical anchor for Xenophon’s account. The attribution of a lost Anabasis to him places him among the participant-historians of his era, highlighting that multiple firsthand accounts of major events were composed, even if few survived.