The Arab certainly was not disposed to regard the conquered alien, even if he embraced Islam, as a brother. To him the conquest of foreign lands meant only the acquisition of vast estates, of great wealth and unlimited power: to him the conquered were simply serfs to be used as a means of rendering the conquered lands more productive. The conquered were allowed the choice either to embrace Islam or to pay the poll tax, but the `Umayyads discouraged conversion as damaging to the revenue, although the cruel and hated Hajjaj b. Yusuf (d. 95) forced even converts to pay the tax from which they were legally exempt. (iii) The third stratum consisted of the “clients” (mawla, plur. mawâlî), the non-Arab converts, theoretically received as brethren and actually so treated by the “old believers,” but regarded as serfs by Arabs of the Umayyad type. Owing to the wide expansion of Islam these rapidly increased in number until, in the 2nd century of the Hijra, they formed the vast majority of the Muslim world. The two first Khalifs were “old believers” who had been companions of the Prophet in his flight from Mecca. The third, `Uthman, had also been one of the Prophet’s companions, but he was a weak man and moreover, belonged to the `Umayyad clan, which, as the aristocratic element in Mecca, was then in the ascendant and, unable to free himself from the nepotism which is an Arab failing, allowed the rich conquests of Syria, Egypt, `Iraq, and Persia to become the prey of ambitious members of the clan and thus suffered the complete secularising of the Islamic state. When, in 35 A.H., he fell a victim to the assassin, he was succeeded by `Ali, one of the older Muslims and the Prophet’s cousin and son-in-law. But at `Ali’s accession the internal division appears as an accomplished fact. The purely secular Arabs, led by the `Umayyad Mu`awiya, who was governor of Syria, entirely refused to recognise `Ali, affecting to regard him as implicated in the murder of `Uthman, or at least as protecting his murderers. On the other hand, the Kharijite sect, claiming to represent the older Muslim type, but in reality mainly composed of the Arabs of Arabia and of the military colonies, who were envious of the power and wealth of the Umayyad faction, at first supported him, then turned against him, and in 41 were responsible for his assassination.