Parthamaspates of Parthia

Parthamaspates was a Parthian prince who ruled as a Roman client king in Mesopotamia, and later of Osroene during the early second century AD. He was the son of the Parthian emperor Osroes I.

After spending much of his life in Roman exile, he accompanied the emperor Trajan on the latter's campaign to conquer Parthia. Trajan originally planned to annex Parthia as part of the Roman Empire, but ultimately decided instead to place Parthamaspates on his father's throne as a Roman client, doing so in 116.Following Roman withdrawal from the area, Osroes easily defeated Parthamaspates and reclaimed the Parthian throne.

After his defeat in Parthia, Parthamaspates again fled to the Romans who then, as a consolation, granted him the co-rule of Osroene, a small Roman client state between Asia Minor and Syria. He was king of Osroene together with Yalur from 118 to 122, and afterwards sole ruler to 123.

• (in French) Clément Huart & Louis Delaporte, L'Iran antique : Élam et Perse et la civilisation iranienne, Albin Michel, coll. « L'Évolution de l'Humanité », Paris, 1943, p. 327.
• Toumanoff, Cyril (1986). "Arsacids". Encyclopaedia Iranica, Vol. II, Fasc. 5. Cyril Toumanoff. pp. 525–546.