Abbasid Caliphate

Definition: Abbasid
An Islamic dynasty established in 750, when it replaced the Umayyad caliphate. Originally based in Mesopotamia (the Abbasids founded Baghdad in 762), it remained dominant in the Islamic world until the mid-10th century.

"Abbasid" was the dynastic name generally given to the caliphs of Baghdad, the second of the two great Sunni dynasties of the Muslim empire. The Abbasids defeated the Umayyad caliphs in battle in 758 and flourished for two centuries.

The Abbasids claimed to the be the rightful heirs to the Caliphate based on their descent from Abbas ibn Abd al-Muttalib (566-652), one of the youngest uncles of the prophet Muhammad.

The Abbasid Dynasty ended in 1258, when the Mongol general Hulagu Khan sacked Baghdad, but they continued to claim religious authority from their base in Egypt.