On the contrary, we know from the historians that in this province Iranian elements remained steadfast throughout the Umayyad dynasty and it was exclusively due to the support given by Khorasanians to the Abbasides that the latter succeeded in overthrowing the previous dynasty and commenced the era of powerful Iranian influences in the history of the Musalman Orient.
"Iranian Influence on Moslem Literature, Part I"
M. Inostranzev