Muhammad al-Nafs al-Zakiyya
Muhammad ibn Abdullah ibn al-Hasan al-Muthana ibn al-Hasan al-mujtaba ibn 'Ali ibn Abi Talib or Muhammad al-Nafs al-Zakiyya (Arabic: محمد بن عبد الله بن الحسن بن الحسن بن علي الملقَّب النفس الزكية, "The Pure Soul") was a descendant of Muhammad through his daughter Fatimah. Known for his commanding oratory skills, amiable demeanor, and impressive build, he led a failed revolt in Medina against the second Abbasid Caliph, Al-Mansur. His followers deserted him and he was left with few hundred of his soldiers against large Abbasid force under Isa ibn Musa, and he was killed on December 6, 762 CE (145 AH).
Initially, he hoped to rebel against Umayyad rule, when the children of Hashim paid their allegiance to him at Abwa. Among them were Ibrahim al-Imam, As-Saffah and Al-Mansur. But it soon became clear that Abbasid rule was established, so those who had paid allegiance to him deserted him, and another group of Shiites flocked around him.
Muhammad was an inspirational figure to many throughout the caliphate who believed that he was destined for glory due to his ancestry. For years he disguised himself and traveled stealthily, since his professed relationship to the Prophet meant that he posed a threat to the established political order. He was eventually able to amass a sizable but ragtag army and seize the city of Medina. He then left Medina in the year 145 A.H and took over Mecca and Yemen (only to be killed in Medina a few months later).
His revolt in 762–763
Medina was an exceptionally poor place for any large-scale insurrection due to its dependence on other provinces for goods, and his motley army of devotees were no match for the Caliph's imperial soldiers. Despite the advantage held by the Abbasid troops, Muhammad refused to step down in the hours before battle, blindly believing that utilizing the historic trenches dug by the Prophet to fortify the city decades earlier would result in victory. His naiveté led to a crushing defeat at the hands of the Abbasids, quelling for the time the possibility that the prophet's family would ascend to political power.
Due to the unrealistically high expectation among his followers of success, a section of his followers were shocked and could not bear the news of his defeat, and did not believe his murder, since they believed he was the Mahdi, whose appearance they had been awaiting for a very long time. They believed he was not killed, but alive and staying on the Mount of Ilmiyyah (between Makkah and Najd) until the time when he would reappear. This section of his followers held onto a hadith of Muhammad, which implies that the Mahdi’s name is like Muhammad’s name and the Mahdi’s father’s name is like Muhammad’s father’s name (Abdallah).