 The position of Persians in the Abbasid caliphal court reached its peak during al-Rashid's reign.The Barmakids were a Persian family (from Balkh) that dated back to the Barmak, a hereditary Buddhist priest of Nava Vihara, who converted after the Islamic conquest of Balkh and became very powerful under al-Mahdi.Yahya had helped Hārūn to obtain the caliphate, and he and his sons were in high favor until 798, when the caliph threw them in prison and confiscated their land.