appointed Quintus Marcius Crispus as governor of Bithynia and Pontus. Following Caesar's assassination on March 15, 44 BC, by the members of the Roman Senate, Marcus Junius Brutus and Gaius Cassius Longinus fled from Italy and assumed command of the Republic's eastern provinces, including Bithynia and Pontus, in 43 BC. When Crispus refused to serve the assassin of his patron, Cassius had him removed from office and forced into retirement. Following the defeat of Brutus and Cassius by the Second Triumvirate at the Battle of Philippi in 42 BC, Triumvir Mark Antony assumed command of the Republic's eastern provinces. The Second Triumvirate expired in 33 BC, ending Antony's legal right to govern the Eastern half of the Republic. With the Triumvirate lapsed, the struggle for dominance between Antony and Octavian intensified. As Octavian built up his support in the West, Antony drew ever closer to Egyptian Queen Cleopatra. When Octavian declared war on Egypt, Antony, supported by the Eastern provinces (including Bithynia and Pontus) went to Egypt's aid against Octavian. Octavian's victory over Antony at the Battle of Actium in 31 BC ensured Octavian's position as undisputed master of the Roman world. In 27 BC, Octavian became "Augustus": the first Roman Emperor. Rump State In 39 BC, Antony stripped control of Lesser Armenia (the remnants of the former Kingdom of Pontus) from the rulership of the Cappadocian king Ariarathes X of Cappadocia and made Darius of Pontus, son of Pharnaces II of Pontus, the Roman client king of Pontus. Antony also granted to Darius the rulership of the Roman client kingdom of Cilicia. His reign lasted until his death in 37 BC, after which Antony appointed Polemon I of Pontus as client king of Cilicia and Arsaces of Pontus as client king of Lesser Armenia. Following Arsaces' untimely death the next year in 36 BC, Antony appointed Polemon I as client king of Pontus. Years later, in 16 BC, Polemon I, at the request of Marcus Vipsanius Agrippa and with the approval of Roman Emperor Augustus, married Queen Dynamis of the Bosporan Kingdom, becoming ruler of that realm in addition to Pontus and Cilicia. Polemone I would later add Colchis to his realm of client kingdoms he ruled on behalf of Rome. Following Polemon I's death in 8 BC, he was succeeded by his stepson Tiberius Julius Aspurgus as client king of the Bosporan Kingdom and by his second wife