Darius. Born about 558 BC, son of Hystaspes, dethroned Smerdis the usurper, and became king of Persia in 521. Darius captured Babylon after a siege of 20 months, conquered Thrace, and defeated the Scythians. He sent two armies to Greece to avenge the destruction of Sardis by the Athenians, the first of which was repulsed by the Thracians, and the second by the Athenians at Marathon in 490. Darius died in 486 BC, while organizing a third expedition.

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