The second caliphate, the Umayyad Caliphate, was ruled by Banu Umayya, a Meccan clan descended from Umayya ibn Abd Shams. The caliphate continued the Arab conquests, incorporating the Caucasus, Transoxiana, Sindh, the Maghreb and the Iberian Peninsula (Al-Andalus) into the Muslim world. The caliphate had considerable acceptance of the Christians within its territory, necessitated by their large numbers, especially in the region of Syria. Following the Abbasid Revolution from 746 to 750, which primarily arose from non-Arab Muslim disenfranchisement, the Abbāsid Caliphate was established in 750.