The Factors Effective in Formation and Expansion Of Twelver Sunnism And it’s Mutual Effect on Shi’sm in the Ninth Century

The present study aims at investigating the factors effective in formation of the Twelver Sunnism in ninth century AH and its mutual effect on Shi’ism. The writers attempt to answer the following questions: “What factors have been effective in the initial formation as well as the expansion of Twelver Sunnism in ninth century AH?” and “What were the mutual effects of Twelver Sunnism and Shi’ism?” The findings of this study, conducted in a descriptive-analytical method, suggest that the fall of Abbasid caliphate as the most powerful Sunni religious institute caused other religious groups, especially the Shi’a groups, to find an opportunity to be active in the political atmosphere of that era and gradually add their followers. Besides, the diffusion of Sufi movements in Iran due to religious tolerance of the Teymurids created a new thought that attempted to pay special attention to Shi’a Imams and a peaceful coexistence between Sunnism and Shi’ism in Iran, while being committed to the Sunni principles. This new thought is known as Twelver Sunnism. Here, Sufism became the vehicle for a trend whose result was a religious transition in Iran from mere Sunnism to Shi’ism in the period between the seventh and ninth centuries.