 During the rule of his father Shapur I, Narseh had served as the governor of Sakastan, Sindh and Turan.Prior to becoming shah of Iran, he held the title of "Great King of Armenia".Narseh overthrew the increasingly unpopular Bahram III in 293 with the support of most of the nobility, which thus makes him the first Sasanian shah to not ascend the throne as a crown prince.