At a quite early date the house of ʿAli began to receive the devoted adherence of the Persian converts. That ʿAli himself had been prominent as a champion of the rights of alien converts to equality in the brotherhood of Islam, and still more his harsh treatment by Muʿawiya, the founder of the ʿUmayyad dynasty, caused his name to serve as a rallying point for all those who were disaffected towards the official Khalifate. It is now the general Shiʿite belief that ʿAli, the cousin and son-in-law of the Prophet, was his chief companion and chosen successor, the three preceding Khalifs being no more than usurpers who had kept him out of his just rights, and whose wrong doing he had borne with exemplary patience. ʿAli himself does not seem to have taken so pronounced a view, but he certainly regarded himself as injured by his exclusion from the Khalifate. It is not true to say with Muir (_Caliphate_, p. 301), that the idea of a divine Imamate or “leadership” was entirely the invention of later times because, as early as A.H. 32, in the reign of ʿUthman, the Jewish convert ʿAbdu b. Saba of Yemen,—a district which had been conquered by the Persian king Nushirwan, and settled by Persians for nearly a century before the coming of Islam, and so thoroughly impregnated with Persian ideas,—preached the divine right of ʿAli. This view he maintained afterwards when ʿAli was Khalif, in spite of ʿAli’s own disapproval, and at ʿAli’s murder in A.H. 40, he reiterated it in a more pronounced form: the martyred Khalif’s soul, he said, was in the clouds, his voice was heard in the thunder, his presence was revealed in the lightning: in due course he would descend to earth again, and meanwhile his spirit, a divine emanation, was passed on by re-birth to the imams his successors. Certainly the tragedy of Kerbela, which centred in the pathetic sufferings and death of ʿAli’s son, Husayn, as he was on his way to claim the Khalifate, produced a tremendous wave of pro-ʿAlid feeling: indeed a popular martyr was the one thing needed to raise devotion to the house of ʿAli to the level of an emotional religion, though many, no doubt, supported the ʿAlid claims simply because they formed the most convenient pretext for opposing the official Khalifate, and yet remaining outwardly within the fold of Islam.