LYCOS RETRIEVER 
Abbasid Caliphate
built 817 days ago
The Zanj revolt is a fascinating moment during the nadir of the Abbasid caliphate. The slave-revolt resulted in a state that eventually minted its own money and enslaved their former Arab master, but the extended revolt was ... one that was the result of large number of extremely bloody massacres--mostly able to do so because the caliphate was too busy with the Saffarids to the East at the time. It's not a nice moment either in the history of central caliphate or in world history generally.
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Abbasid was the dynastic name generally given to the caliphs of Baghdad, the second of the two great dynasties of the Muslim empire. The Abbasid caliphs officially based their claim to the throne on their descent from Abbas (AD 566-652), the eldest uncle of Muhammad, in virtue of which descent they regarded themselves as the rightful heirs of the Prophet as opposed to the Umayyads, the descendants of Umar.
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Imam Hasan ibn Ali 'Askari, the son of the tenth Imam, was born in 232/845 and according to some Shi'ite sources was poioned and killed in 260/872 through the instigation of the Abbasid caliph Mu'tamid. The eleventh Imam gained the Imamate, after the death of his noble father, through Divine Command and through the decree of the previous Imams.
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Abbasid Caliphate