Wilhelm Barthold misidentified him as the son of
Nasr ibn Sayyar, the last
Umayyad governor of
Khurasan, but according to the
Kitab al-Aghani and other sources, Layth and his brother Mu'alla were the sons of a certain Tarif, a slave or client (
mawla) of the
Abbasid caliph
al-Mansur (r. 754–775). Layth and his brother were purchased as slaves by al-Mansur and given to his heir
al-Mahdi (r. 775–785), who set them free. Layth is first mentioned as commanding an army against the king of
Farghana under al-Masnur, while al-Mahdi sent him against the Iranian rebel
al-Muqanna. Later al-Mahdi appointed him as governor of
Sind. He was recalled during the brief reign of
al-Hadi (r. 785–786), but reinstated to the post by
Harun al-Rashid (r. 786–809). Either he or
Layth ibn al-Fadl were governors of
Dinawar in 796/7. == References ==