Hystaspes or Guštāsp, 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 w
A "Niebuhr inscription" reading "Darius the Great King, King of Kings, King of countries, son of Hystaspes, an Achaemenian, who built this Palace".
Position of Hystaspes in the Achaemenid lineage according to Darius the Great in the Behistun inscription.
According to Ammianus Marcellinus, Hystaspes penetrated deep into India, where he learned from the Brahmins. Historically, this corresponds to the time of the Achaemenid conquest of the Indus Valley.
Darius In Parse