Yahya Ibn Khaled Barmaki
Yahya ibn Khaled (died 806) was a member of the powerful Persian Barmakids family, son of Khalid ibn Barmak. Around 765, he was appointed to Azerbaijan by the Caliph Mansur. When Hadi was Caliph, Yahya dissuaded the Caliph several times from proclaiming his own son as heir instead of Harun. He eventually did so, and cast Yahya into jail, but died shortly after. When Harun became Caliph as Harun al-Rashid, he made Yahya Vizier. Under his influence, the Caliph invited to Baghdad many scholars and masters from India, especially ####Buddhists. He had three sons, among which Jafar succeeded him as Vizier, Musa ruled Damascus, and Fadl was governor of Khurasan, then of Egypt. In 803 his family fell into disgrace, and he was cast into prison, where he died in 806 (according to the story, because his son Jafar had an affair with Harun al-Rashid's sister, most likely because the family had too much power).
Sources :
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