The Factors behind the Spread of Twelver Shiism in Beihaq (Sabzevar) from Its Beginning to the Mongol's Invasion

Beihaq is a name given to the ancient name of Sabzevar, which was, like Qom and Kashan, among the poineering cities that embraced Shiism. The roots of Shiism in Beihaq traces back to the first century AH. The present paper investigates the time of and the factors o bihind the spread of Twelver Shiite beliefs in Beihaq from early Islam until the Mongol's invasion in 617 AH. Among these factors are the presence of Qanbar’s clan and some of the holy Prophet's Companions in Beihaq, the arrival of Imam Reza (peace be upon him) in Neyshaboor and Tus which are near Beihaq, Beihaqi people's support for Yahya ibn Zeid's uprising, the presence of Shia scholars and books in this city, the migration of the descendents of the Prophet to this land, its people's love and affection for the holy Prophet's family, and the widespread of Shia poems.