He saved the kingdom from the Mongolian Sacae (Tochari), who had occupied Bactria and eastern Iran, and is said to have extended the limits of the empire (Justin 42, 2, where he is afterwards confused with Mithradates III).
He defeated King Artavasdes of Armenia and conquered seventy valleys; and the prince Tigranes came as hostage to the Parthians (Justin 42, 2; Strabo, xi. 532). In an inscription from Delos he is called "the great King of Kings Arsakes."
He also interfered in the wars of the dynasts of Syria (Jos. Ant. xiii. 14, 3). He was the first Parthian king who entered into negotiations with Rome, then represented by Sulla, praetor of Cilicia in 92 BC.
This entry was originally from the 1911 Encyclopedia Britannica.