ALMANSOR the Victorious, the second caliph of the house of Al Abbas, succeeded his brother Abul Abbas Al Saffah, in the year 753, of the Hegira 136, and in the following year was inaugurated at Al Haflimiya. Although Al Saffah had declared him presumptive heir of the crown, and he had been proclaimed caliph in the imperial city of Anbar, yet immediately upon his inauguration, his uncle Abdallah ibn Ali had sufficient interest to cause himself to be proclaimed caliph at Damacus. In Arabia, Syria, and Mesopotamia, he collected a numerous army, and arrived at the banks of the Masius, near Nilibis, where he encamped, ready to dispute his royal accession by arms. Almanfor collected an immense army in Persia, Khorasan, and Irak, and gave the command of it to Abu Moalem, who harassed his uncle's troops for five months, and at last totally defeated him, A.D. 754. Notwithstanding the services which Abu Moalem had rendered to the family of Al Abbas, after this victory he became an object of jealousy, and was assassinated in the presence of Almanfor himself, by his express order. After the death of Abu Moalem, the standard of rebellion was raised by Simon a Magian, who seized on the treasures of the deceased governor of Khorasan, and excited the people of that country to a general revolt; but this insurrection was suddenly quelled by the general of Almanfor, Jamhur ibn Morad. The caliph avariciously seized the spoils of this victory, which so incensed Jamhur that he immediately turned his arms against his royal master; but he was soon defeated by the caliph's forces. The patriarch of Antioch was about this time detected in an illicit correspondence with the Grecian emperor, and consequently was banished into an obscure part of Palestine; and in the mean time the Christians in the dominions of the caliph were prohibited from building or repairing any churches, and also were laid under several other severe restraints.

Almanfor sent a large army into Cappadocia in the year 757, fortified the city of Malatia or Melitene, Almanfor, licene, and depolished in it a great part of his treasurers. But in this year he was attacked by a sect of believers in the metempsychosis, called the Rawandians. This sect assembled at Al Hafshimiyah, the residence of the caliph, and by the ceremony of going in procession round his palace, intimated their purpose of invoking him as a deity, and paying him divine homage. Influenced by their impiety, the caliph ordered several of these sectaries to be imprisoned, which roused their resentment, and led them to form the design of his assassination. The generous interposition of Maan ibn Zaidet, an Omriyan chief, who had been under the necessity of concealing himself from the caliph's resentment, however, defeated their intention. This insult received in his capital, induced him to build the city of Bagdad, and to fix his residence there, A.D. 762. In the preceding year a plan was formed to dethrone him; but it being discovered, he severely punished all who were either directly or indirectly concerned in it. Abdullah his uncle shared the fate of other rebels: for being allowed to court under the promise of pardon and protection, he was placed in a building which was so constructed that it immediately fell and crushed him in its ruins. Not long after his residence at Bagdad, he was seized with a disorder of which he was cured by the advice of a famous Christian physician, whose name was George ibn Baktiiluha Al Jondaburi. The caliph, previously informed that he was married to a wife old and infirm, as a reconciliation presented him with three beautiful Greek girls, and a considerable sum of money; the girls, to the caliph's surprise, were sent back, with a declaration on the part of George, that it was not lawful for a Christian to have more wives than one at a time. The conduct of the physician, on this occasion, raised him in the esteem of the caliph, and procured him a greater profusion of favours. In his succeeding military transactions, Almanfor was generally victorious. His conduct to his Christian subjects was rigorous and severe. He set out on a pilgrimage to Mecca in the year 774, and being seized on the road with a dangerous disease, he sent for his son and intended successor Al Mohdi, and gave him some salutary advice. "I command you," said he, "to treat publicly your relations with the greatest marks of distinction, since this conduct will reflect no small degree of honour and glory upon yourself. Increase the number of your freedmen, and treat them with all kindness, as they will be of great service to you in your adversity; but neither this nor the other injunction will you fulfil. Enlarge not that part of your capital erected on the eastern bank of the Tigris, as you will never be able to finish it; but this work I know you will attempt. Never permit any of your women to intermeddle in affairs of state, or to have any influence over your councils; but this advice I know you will not take. These are my last commands; or, if you please, my dying advice; and to God I now recommend you." In parting they both gave vent to their feelings in a flood of tears. He purified his journey to Bir-Maimun, i.e., the well of Maimun, where he died, in the 63rd year of his age and the 29th of his reign, and his remains were interred at Mecca.

The character of Almanfor was formed of very different and even contradictory qualities. His temper conciliated affection and attachment in private life, but in his public character his aspect and demeanour inspired terror. He was well acquainted with the arts of government; he was prudent and brave, but perfidious, covetous, cruel, and implacable; and amid such a variety of character, it is singular that he should have displayed a love of study and literature, and particularly of astronomy. (Gen. Biog.)