Vologases III of Parthia claims the throne of the Parthian Empire about 105, in the last days of Pacorus II of Parthia (80–105).

He reigns over the eastern portion of the kingdom from 105 to 147.

The period is one of civil war in the Parthian kingdom; for the early part of his reign Vologases III contends with Pacorus II's legitimate successors Osroes I (105–116 and 117–129), Parthamaspates (116–117), and Mithridates IV (129–140), who rules Mesopotamia.