The third Abbasid caliph, who consolidated the young dynasty, lavished patronage on Baghdad, and pursued the Manichaean "heretics" (zindiqs) in a drive for orthodoxy.
Life
Al-Mahdi (reigned 775–785), son of al-Mansur, presided over a prosperous consolidation of Abbasid rule. He expanded the administration and pilgrimage roads, patronized poets and scholars, campaigned against Byzantium, and launched an inquisition against dualist zindiqs. His reign strengthened the caliphate and prepared the ground for the golden age under his son Harun al-Rashid.