Cleomenes I (lived 6th–5th century BC)

Spartan king (ruled about 510–490 BC). He was successful in the expulsion of the tyrant Hippias (ruled 527–510 BC) from Athens but failed when he led a small Spartan force to oust Cleisthenes from Athens 408 BC, being besieged on the Acropolis and compelled to withdraw. He decisively defeated Argos at the battle of Sepeia 494 BC. He was forced to flee from Sparta 491 BC when his bri bery of Delphian priestesses, to secure the deposition of his fellow-king and opponent Demaratus, was discovered and he committed suicide a year later. By this date, he may have become mentally unbalanced.