In the period of the second caliph the Muslims whose goal was to conquer Iran, were seeking a place that in addition of being near to Iran could be a proper place from the aspect of weather for the inhabitants of Arabian peninsula. For this reason after writing a letter to the second caliph, sa'd b. Abivaqqas gave a mission to Persian Salman and Hadighat b. yaman to find a proper place for their own and their camel herds. Following this mission a region on the East Coast and near the ancient city of Hireh, which later called kufa, was chosen, and this was the first city that the Muslims built it after the appearance of Islam
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