Arsaces was the second son and youngest child born to King Pharnaces II of Pontus[1][failed verification] and his Sarmatian wife.
[2] His paternal grandparents were the Pontian Monarchs Mithridates VI and his first wife, his sister Laodice.
In 37 BC, Darius had died and Arsaces succeeded his brother as king of Pontus.
According to Strabo, in Arsaces’ reign “he played the role of the sovereign and excited rebellion without the permission of a Roman prefect”.
[2] Mark Antony put on the Pontian throne as Arsaces’ successor, Polemon I.