Darius I, called The Great 558-486 BC, King of Persia (521-486 BC), son of the persian noble Hystaspes, and a member of a royal persian family, the Achaemenids. The first two years of his reign were occupied with suppressing rebellions, the most important of which occurred in Babylonia. Thereafter he devoted himself to reforming the internal organization of persia and making its outer borders secure. He reorganized the vast empire into 20 satrapies, built highways, organized a postal system, reformed the currency, encouraged commerce, and won the goodwill of large portions of the heterogeneous population.
Because he respected their religions, he was honored by the Jews, whom he permitted to complete the rebuilding of the temple at Jerusalem in 516; by the Egyptians, whose high priest he consulted; and by the Greeks of Asia Minor, whose oracles supported him during the revolt of the Greek cities. Darius left a detailed account of his reign, inscribed in three languages on a towering rock. This behistun inscription, the first english transcription if which was complete in 1849, confirms many details of the life of Darius.