Hystaspes (father of Darius I)

Vishtaspa (fl. 550 BC), known under his Hellenized name Hystaspes (Ὑστάσπης), was a Persian satrap of Bactria and Persis. He was the father of Darius I, king of the Achaemenid Empire, and Artabanus, who was a trusted advisor to both his brother Darius as well as Darius's son and successor, Xerxes I.
The son of Arsames, Hystaspes was a member of the Persian royal house of the Achaemenids. He was satrap of Persis under Cambyses, and probably under Cyrus the Great also. He accompanied Cyrus on his expedition against the Massagetae. But he was sent back to Persis, to keep watch over his eldest son Darius, whom Cyrus, in consequence of a dream, suspected of considering treason.
Besides Darius, Hystaspes had two sons, Artabanus and Artanes. Ammianus Marcellinus makes him a chief of the Magians, and tells a story of his studying in India under the Brahmins. His name occurs in the inscriptions at Persepolis.