Bilad al-Sham (Arabic: بِـلَاد الـشَّـام‎, romanized: Bilād al-Shām), often referred to as Islamic Syria or Syria in English-language sources, was a super-province of the Rashidun, Umayyad, Abbasid, and Fatimid caliphates. It roughly corresponded with the Byzantine Diocese of the East, conquered by the Muslims in 634–647. Under the Umayyads (661–750) Bilad al-Sham was the metropolitan province of the Caliphate and different localities throughout the province served as the seats of the Umayyad caliphs and princes.