 Around 208 Vologases VI succeeded his father Vologases V as king of the Arsacid Empire.He ruled as the uncontested king from 208 to 213, but afterwards fell into a dynastic struggle with his brother Artabanus IV, who by 216 was in control of most of the empire, even being acknowledged as the supreme ruler by the Roman Empire.Artabanus IV soon clashed with the Roman emperor Caracalla, whose forces he managed to contain at Nisibis in 217.