|Biographical detail : ||The second Abbaside Caliph and the real founder of that dynasty who moved the capital of the empire to the new city of Baghdad.
Caliph al Mansur a great grandson of Abd-al-Abbas, uncle of the Prophet, peace be upon him, came to the throne after the death of his brother al-Saffah. In 756 he got Abu Muslim, the revolutionary leader who had brought the Abbasides to power, killed. This was the beginning of a series of revolts against him, but he suppressed them successfully.
Due to the Umayad influence in Syria, al-Mansur shifted his capital from Damascus to a newly created city, Madinat al-Salam, the City of peace, called Baghdad, which he built in part of materials taken from the nearby old Iranian capital of Ctesiphon. The City of peace grew in size and importance. Openness and toleration thus ran right through Baghdad’s golden age, when so much groundwork was being done in medicine, mathematics, philosophy, geography and other branches of science. Baghdad was to become where merchants, theatre-types, writers, scientists, astrologers and alchemists were flocking to like now flock to the capitals of the West, because it was so open, and such was a kaleidoscope of humanity.
Caliph al-Mansur’s minister was Khalid ibn Barmak, who inaugurated the influence of the Barmacides in Baghdad and who in later years became more powerful than the Caliph.
Caliph al-Mansur was born Abu Jafar Ibn Muhammad.