Ibráhím deemed himself already a sovereign, and spent his time with a wife whom he had just married. Mansúr, on the other hand, never looked on the face of woman till the conflict was over. A contemporary praises, in eloquent words, the courage and determination which he maintained in his critical position. The advice to incite Cufa to revolt was set aside by Ibráhím because such a step would cause much harm to children, women, and other non-combatants. In the same spirit he forbade pursuit of fugitives, and so forth. All this sounds very well, but is out of place in one who, for his own interests, is carrying on a rebellion which, under any circumstances, must involve much bloodshed, and can ultimately achieve success only by concentration of every energy. In such tenderness there is more of weakness than of humanity. “Thou desirest the sovereignty, yet darest not to slay!” some one said to him. _Pour faire des omelettes il faut casser les œufs._
Soon after the middle of December 762, Ibráhím received the crushing intelligence of his brother’s death. Yet if even now he had advanced immediately, he would still have been able to put Mansúr to great straits. But when he finally marched towards Cufa with barely 10,000 men, a sixth or a tenth of his strength on paper, Isá had already arrived at the head of a superior army. The Caliph had ordered troops from Media against Susiana, which soon captured the capital Ahwáz. In Bákhamrá, only sixteen hours south of Cufa, the army of Ibráhím, who had now assumed the title of Caliph, encountered the advancing host of Isá (Monday, 14th February 763). Mansúr’s vanguard was driven back; but Isá held his ground, and the fugitives soon rallied. Mansúr’s cousins, the sons of Sulaimán, fell upon Ibráhím’s rear. After a fierce battle he fell, mortally wounded with an arrow. The Caliph caused his head also to be publicly exhibited, but would not suffer a bystander to treat the dead with contumely. He punished with frightful cruelty a coarse person who had spat on Ibráhím’s head in his presence.
A victory for Ibráhím seems to have been widely counted upon. The famous blind poet, Basshár, no sectary, but an enlightened freethinker, had sent him a poem, in which he was praised, and Mansúr violently attacked; after the battle he so altered the poem, that he was able to give it out as an earlier production directed against Abú Moslim.