Cleomenes I

(died 491 BC) Spartan king (519–491). An Agiad (descendant from the legendary founders of Sparta), he ruled jointly with Demaratus. In 510 he expelled the tyrant Hippias from Athens, then supported the oligarchic party against the democratic Cleisthenes and refused to help Athens combat Persia. His policies did much to solidify Sparta's position as the leading power in the Peloponnesus. He bribed the oracle at Delphi to depose Demaratus, but he was discovered and fled. Though reinstated, he went insane and committed suicide.

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