Mansúr can hardly have reached the neighbourhood of the Euphrates when he learned that he had a very dangerous rival. His uncle Abdalláh,[[26]] then posted in the far north of Syria ready to march against the Byzantines, laid claim to the throne. His pretensions, perhaps, were not altogether unfounded, for it is not so certain as is usually asserted that Saffáh nominated Mansúr as his successor. It was indeed unfortunate that the dynasty was hardly established before it was torn asunder by disputes about the succession. As Abú Moslim with the Khorásánians held by Mansúr, Abdalláh was compelled to rely upon the Arab troops of Syria and Mesopotamia, and on this account caused thousands of Khorásánians who were with him to be massacred. Humaid, son of the Arabian general Kahtaba, who five years previously had led the Khorásánian troops from victory to victory, suddenly went over from Abdalláh to Mansúr, and rendered to the latter conspicuous service both in this and in many subsequent wars. Abú Moslim brought an end to the war which had been going on for some months in Mesopotamia by a victory gained on 26th (or 27th) November 754. Abdalláh fled to his brother Sulaimán, Mansúr’s governor in Basra (near the mouth of the Tigris), and remained here in hiding for some time.
Abú Moslim thus had not only set up the Abbásid dynasty, but also had saved the throne for Mansúr. A man who had done so much could do still more, and was a danger to his master. Mansúr resolved to get rid of Abú Moslim, a course which is said to have suggested itself even to Saffáh. How they first fell out is told in various ways. It is probable that the Caliph nominated Abú Moslim to be the governor of the western provinces of Syria and Egypt in order to keep him at a distance from Khorásán, where his power had its root, but that the latter did not agree to this. In any case he had noted that Mansúr wished to deprive him of influence, and he resolved accordingly, without reference to Mansúr, to return to Khorásán. Of his own soldiers he was perfectly sure, even in a campaign against the Caliph. At this stage a correspondence took place between the two. Abú Moslim in the end suffered himself to be befooled by the sworn assurances of Mansúr (with a slight admixture of threats), and came with but a small following to the Caliph at the “city of the Romans,” a decayed place that had belonged to the Seleucia-Ctesiphon group of Persian royal cities. Mansúr received him graciously, but after having made sure of him, caused him to be slain before his eyes, and the body to be cast into the Tigris (February 755).
The removal of the powerful individuality, of whom we hear that his followers would have sacrificed their lives and their very souls for him, but upon whose fidelity the Caliph could hardly rely, was a political necessity. An intimate of Mansúr’s is said to have quoted to him against Abú Moslim the verse of the Koran in which it is said that if the world held other gods besides Alláh it would go to ruin (súra 21, 22). Such a prince as Mansúr could tolerate no rival in the kingdom. Nor can any great claim upon our pity be made for Abú Moslim, who shrank from no resource of violence or treachery, whether against enemies or against inconvenient friends, and of whom it is said (no doubt with huge exaggeration), that he caused as many as 600,000 prisoners to be slain. Mansúr gave proof of admirable astuteness when he overreached the cunningest of the cunning. But that his conduct was abominable goes without saying.
The murder was by no means without danger for its perpetrator. The soldiers indeed whom Abú Moslim had brought with him were restrained from making any disturbance, partly by their dismay at the accomplished fact, and partly by a lavish distribution of money. But mutterings were heard in Khorásán. There the dead man had thousands who clung to him with religious attachment. In fact, there were many who could not believe in his death, and who expected him to return once more as a Messiah. A Persian named Sampádh excited in that very year a great revolt in Khorásán to avenge Abú Moslim. What is reported of him, that he was a professor of the old Persian religion, is improbable; he may have belonged to one of the half-Persian sects, which the majority certainly could not regard as Mohammedan. In any case the revolt was a popular movement. Sampádh advanced far towards Media, but thereupon was defeated by Jahwar, whom Mansúr had despatched against him, and slain somewhere near the spot where the last of the Dariuses met his end. The victorious general had made himself master of the treasures of Abú Moslim, and now in turn himself rebelled, but was quickly overcome, and put to death (755 or 756). Khorásán was once more securely in the hands of the Caliph.
In other directions also disturbances of various kinds occurred. The Kharijites,[[27]] who had no reason for regarding the rule of the Prophet’s kinsmen as juster or more in accordance with the laws of God than that of the Omayyads, fought on for their ideals in various parts of the empire, with few followers indeed, but with a courage that defied death. Thus a certain Kharijite, Mulabbid, in Mesopotamia gave much trouble to the armies of the Caliph, and was only at last overcome in 756 by Házim, perhaps the ablest of Mansúr’s generals.
A handful of strange mortals brought the Caliph into a very difficult position, probably in 757-8. The Ráwendí, who are guessed to have been connected with Abú Moslim, not only believed in the transmigration of souls, but had also taken into their heads that Mansúr was God Himself. They accordingly betook themselves to his capital, and set themselves in an attitude of worship around his palace. Mansúr, indeed, was quite of the mind that it was better to have people obey him and go to hell in consequence, than earn heaven by rebellion against him; but the Commander of the Faithful durst not tolerate such conduct as this of the Ráwendí, unless he wished to provoke a universal rising of all Moslems against him. He accordingly caused a number of the fanatics to be imprisoned. But they did not take this well; they freed their comrades and now assailed the life of the Caliph, who only had a limited guard at hand. In mastering them, which he did only with difficulty, he displayed great courage. In the struggle there came to the front one who had been a conspicuous general under the Omayyads, afterwards had kept himself in concealment, and now seized this opportunity to gain favour with the Caliph. This was Maan, son of Záida, famed for his bravery, and still more for his liberality, but at the same time stern and pitiless towards his foes. Mansúr, whom it thoroughly suited to intermingle pure Arabs with his Khorásán generals of mixed Arabian and Persian origin, willingly took the fire-eater into his grace. Shortly afterwards he sent him into Yemen, where, during his nine years’ governorship, he subdued all opponents with much bloodshed. Subsequently he sent him to south-eastern Persia, where he was surprised and slain by the Kharijites.
The dynasty of the Omayyads once overthrown, the Alids saw that they had not gained much. It made no difference to them whether their nearer cousins, the descendants of Abbás,[[28]] or whether their slightly more distant kinsmen, those of Omayya, possessed the sovereignty; the name of Háshim was not enough. When the house of the Prophet had been canvassed for, every one in the first instance had thought of his actual descendants; these last now deemed, not unrightly, that they had been defrauded of their birthright. It is probable that even the Abbásids, in the secret negotiations, at an early stage had at one time freely acknowledged the Alid Mohammed, son of Abdalláh, as head of the entire house, and as the future Caliph. Why this particular man should have been selected from among the very numerous descendants of Alí, we are unable to say. One advantage, which fell into the scale when a legitimist claim was being urged, he undoubtedly had—namely, that the females also who came into his genealogy were all free Arabs of good family, and that the Hasanid Mohammed was through his grandmother a descendant also of Husain, and thus in a twofold way descended from the Prophet.[[29]] His father, who might have advanced still stronger claims, was perhaps over-timid or too little ambitious.
The Abbásids knew too well how it was that they themselves had reached the throne to be other than exceedingly jealous of the hereditary advantages of their cousins. One and another Alid now and again expressed tolerably openly his opinion of the situation. And the Mohammed just mentioned, as well as his brother Ibráhím, had betrayed themselves by refraining to come to pay their respects to Mansúr when he made the pilgrimage during the lifetime of his brother. If Mansúr actually had at one time acknowledged Mohammed’s right to the caliphate, this would be to him a further motive for effort to have them in his power. But neither promises nor threats availed; they hid themselves in various quarters of Arabia, and are said to have wandered about in even remoter lands. As their father when closely questioned persisted in declaring that he had no idea where his sons were living, Mansúr, when he came on pilgrimage once more to Mecca in April 758, caused him to be imprisoned. But even this did not avail. The governors in Medina either could not or would not find the fugitives. The inhabitants were attached to the Alids as being children of the Prophet and children of their city, and the majority of the officials even would doubtless have felt it to be a crime to deliver them up to destruction. Riyáh, however, of the tribe of Morra, who entered upon the governorship of Medina on 27th December 761, was free from any such weakness. He threatened the inhabitants with the same fate with which, sixty-eight years before, his fellow tribesman Moslim, son of Okba, had visited their rebellion against authority.[[30]] He caused all the nearer kinsmen of Mohammed’s family, and many of his adherents, to be imprisoned, and also a number of the Juhaina Bedouins, among whose mountains, to the west of Medina,[[31]] it was supposed that the claimant was in hiding. When, at the close of another pilgrimage (March 762), Mansúr visited Medina, he took these captive Alids, including the father of the two brothers, and various other persons of consideration, and carried them with him in chains into Babylonia. Amongst these exiles was the step-brother of Abdalláh, who secretly, and in violation of his plighted word, had given his daughter in marriage to his nephew, the claimant, and is said also to have himself seemed formidable by reason of his personal distinction as a descendant of Caliph Othmán. A son of Mohammed’s fell into the hands of the governor of Egypt, and was sent to the Caliph. We can readily believe what we read, that the treatment of these hostages was by no means indulgent;[[32]] several were put to death, many died in prison. But popular imagination, or personal hatred, has raised the colours of the picture; the story goes that the Caliph kept the bodies of all the murdered Alids in a great chamber to which no one had access but himself; in the ear of each was a label with his name and genealogy neatly written. Mansúr’s son Mahdí ventured to use the key after his father’s death, and, horrified at the discovery, caused them all to be buried.
Riyáh’s diligent search seems at length to have led Mohammed to attempt a premature revolt, which towards the end of 762 broke out in Medina. Mohammed was proclaimed Caliph, the captives set free, the governor and other adherents of Mansúr thrown into prison. The famous doctor of Islam, Málik, son of Anas, gave his decision that the oath of allegiance to the Abbásids, having been obtained by force, was of no binding obligation. This is characteristic at once for the ethics of Islam and for the view of the rule of the Abbásids which was taken by those persons who were, properly speaking, the guardians of religion and of the sacred law.[[33]] At Málik’s dictum everybody went over to Mohammed. Even the descendants of Abú Bekr and other men of Koraish, who had formerly distinguished themselves at the founding of the empire of Islam, for the most part joined him. So also did the poet Abú Adí al Ablí, who belonged to a side branch of the house of Omayya. These individuals, however, seem to have inherited but little of the statesmanlike and warlike ability of their ancestors. From the very first many clear-headed men saw that the enterprise had small prospect of success. When a volunteer courier, in the extraordinarily short space of nine days, brought news of the insurrection to Mansúr at Cufa, he was far from dissatisfied with this clearing of the situation. “Now, at last,” said he, “I have the fox out of his hole!” Medina was of all places least suited for the foundation of an anti-caliphate,—for this, among other reasons, that the whole region was dependent on imports from Egypt, the supply of which was now at once cut off. Mansúr sent his cousin Isá, son of Músá, with a small but tried army against Medina. Mohammed proved no more equal to his task than the other Alid pretenders had done. Instead of taking the advice of persons skilled in war, and assuming the offensive, he remained within the city of the Prophet, the sanctity of which he took to be his best defence: once, in a dream, it had appeared to the Prophet under the figure of a breastplate. By way of fortification he caused the fosse of the Prophet to be restored; a work which indeed had filled with astonishment the Arabs combined against Mohammed,—men who had had no experience of war on a large scale, or indeed of any kind of strenuous united action,—but which was mere child’s play for the veterans of Khorásán. Isá had already, by letters, won over from Mohammed various important persons. The great bulk of his followers quietly melted away as the foe drew near. Isá paused for three days before Medina, to obtain, if possible, an amicable settlement by negotiation, and operations then began. The fosse was bridged with some house-doors. A woman of the family of Abbás secretly caused a large black cloth to be hoisted on the tallest minaret; upon this all the pious townsmen immediately rushed to the conclusion that the Khorásánians had entered the city by the rear, and there had planted the black banner of the Abbásids. Only a few, including a company of Juhaina Bedouins, stood by Mohammed. Mohammed, a tall and handsome man, fell after a heroic struggle late on the afternoon of Monday, 6th December 762. He had caused the captive Riyáh to be put to death immediately before. One more addition was thus now made to the roll of Alid “martyrs,” who had inherited from their ancestors courage and bravery, but with these also an incapacity for generalship and supreme command. The supporters of the house surnamed Mohammed as “the pure soul.”
Isá, obeying orders, showed comparative clemency. It was of importance to the descendants of Abbás that the sanctity of the city of the Prophet, to whom they traced back their rights, should not be violated too grossly. Some prominent participators in the rebellion, indeed, were put to death, or else imprisoned or subjected to severe corporal chastisement. The goods of that branch of the Alid family to which the pretender had belonged were confiscated. According to the custom of the time, his head was brought to the Caliph, who sent it by courier-post round the provinces as an awful example. It arrived in Egypt in the spring of 763, just in time to check a rising of the Alid party there.