The policies of the Abbasid Caliphate, the factors influencing the military instability of Khorasan (in the years 259 to 287 AH)

In the second half of the 3rd century of Hijri, Khorasan was the battlefield of warring military forces for more than two decades. By overthrowing the Taherian, the Saffarian sought to consolidate their rule over Khorasan, and after the fall, the Taherian were trying to revive their government based on the acceptability and legitimacy of the Abbasi caliphate charter and using former military personnel. Due to the lack of legitimacy, the military commanders sought refuge with the Tahirian and read a sermon in the name of Muhammad bin Tahir. The conflict between these forces resulted in the political and military instability of Khorasan. The Abbasi caliphate, based on its legitimizing power, granted the charter or disapproved of the antagonists based on their interests and interests. This approach of the caliph was one of the factors affecting the lack of definite superiority of one of the parties and numerous campaigns, which caused the military instability of Khorasan in this historical period. The present article, written with a descriptive-analytical approach and based on first-hand historical sources, aims to answer the question of what role the policies of the Abbasid Caliphate played in the military conflicts of Khorasan in the second half of the third century. The findings of the research show that the necessity and expediency was the main motivation of the Abbasid caliphate in adopting a policy against the political and military events of Khorasan, and this was the approach of the influential authors along the military disturbances of Khorasan in the second half of the third century AH.