The Abbasid Caliphate ( or ) was the third of the Islamic caliphates to succeed the Islamic prophet Muhammad. The Abbasid dynasty descended from Muhammad's youngest uncle, Abbas ibn Abd al-Muttalib (566–653 CE), from whom the dynasty takes its name. They ruled as caliphs, for most of their period from their capital in Baghdad in modern-day Iraq, after assuming authority over the Muslim empire from the Umayyads in 750 CE (132 AH).