[1] 1st cent. AD Parthian king
Son of Vologaeses I, who fought Pacorus for the Parthian crown from AD 89/90, but did not succeed until 108/9. His meddling in Armenia (cf. Axidares; Parthamasiris) provoked Trajan's Parthian War (Parthian and Persian Wars), which O. weathered despite severe setbacks. In 117, he expelled his son Parthamaspates, who had been drawn to the Roman side and whom Trajan had made king of the Parthians. A treaty was concluded at a m…