 Besides, unrest flared up in Yemen, and the Kharijites rose in rebellion in Daylam, Kerman, Fars and Sistan.Revolts also broke out in Khorasan, and ar-Rashid waged many campaigns against the Byzantines.Ar-Rashid appointed Ali bin Isa bin Mahan as the governor of Khorasan, who tried to bring to heel the princes and chieftains of the region, and to reimpose the full authority of the central government on them.