The eastern part of Sistan was not been conquered simultaneous the Arab dominance on Iran‚ under patronage of Zumbils‚ and the natives resisted against Muslims’s armies attaks. But‚ by the mid of 3th century‚ Islamic teachings were penetrated in this area‚ as a preraililng religion.
By historical descriptive – analytic method and asking about the little existing data‚ this article seeks to make much clear‚ if possible‚ the process problem of Islam expansion in Zunbil’s dominion. This study shows that‚ although‚ the Zunbils resisted against the Islamic armies‚ but gradually that area was affected by Islamic Culture and teachings in different ways‚ as religious propaganda of Muslim merechants‚ holy Warriors (ghazis) ‚ political socialization‚ above all‚ efforts of the Khawarij there‚ and their final military vim was crushed by Saffarids.