​NICOMEDES III., Philopator, king of Bithynia, 91–74 B.C., was the son and successor of Nicomedes II. His brother Socrates, assisted by Mithradates, drove him out, but he was reinstated by the Romans (90). He was again expelled by Mithradates, who defeated him on the river Amneus (or Amnias) in Paphlagonia. This led to the first Mithradatic War, as the result of which Nicomedes was again restored (84). At his death he bequeathed his kingdom to the Romans, a legacy which subsequently brought about the third Mithradatic War.