The Arab rulers had adopted a number of radical measures for the Arabization and Islamification of Iran which created disaffection among the Iranian population. As Bulliet’s study demonstrates, only a small proportion of Iranians had converted to Islam on the eve of the Abbasid revolution; as a result, the new policies of the Muslims in the 8th century had had a drastic impact on the nonMuslim population, still the majority in Iran. At this time, the population of northern Khurasan was particularly rebellious. The damage caused by the Muslim conquerors in the area was considerable and still fresh in the memory of the local people who had been forced to accept Islam and who, despite their conversion were still forced to pay large tributes. It is therefore not surprising that the dissident movements began in Khurasan before spreading westwards. The earliest of these movements commenced concurrently with the Abbasid revolution and was led by Bihafrid Mahfravardan. There has been a long debate over the religion of the insurgents; however, in the case of Bihafrid Mahfravardan there is no doubt of his being Zoroastrian. The opposition of the conservative Zoroastrian clergy to his political and social activities shows that Bihafrid adhered to another faction of the Zoroastrian Church. Abu Muslim, the famous leader of the Abbasid revolution was able to take advantage of the divisions among the Zoroastrians to kill Bihafrid two years before the fall of the Umayyads. The successes of Abu Muslim against the unpopular Umayyads had won him allies not only among the Muslim minority but also among the Zoroastrian majority, who hoped for an improvement of their condition. Abu Muslim, however, did not provide the Zoroastrians with much option other than conversion to Islam. The involuntary nature of these conversion becomes manifest right after the death of Abu Muslim in 754, when there was a surge in apostasies and revolts in Iran (Source: the Fire, the Star and the Cross).