Role of political and official variables in boundary changes of Khorasan, in first 5 centuries after Hijrat

The important situation of Khorasan in first 5 Islamic centuries, invites the researcher of this subject to scrutiny concerning the actual model of Khorasan in the centuries aforementioned. Issues like: what changes have been applied to the geographical boundaries of Khorasan? And what were these changes affected by? These are the issues by which that this state has been affected by in this section. This paper tries to prove this point of view that geographical boundaries of Khorasan in the period just mentioned, is a function of official system and politicalconditions of this state and by changes to these variables, Khorasan’s boundaries will also incur modifications. If the researcher of Islamic history ignores these amendments, he/she will be misled to a false understanding of the events in the analysis of historical changes to Khorasan. Geographical boundaries of Khorasan in first and second Hijri centuries is a function of official system belonging to Sassanid reign and by formation of Taheri and Samani periods in this state, changes relevant to new political and official conditions in Khorasan will occur that mostimportant of them is the change to official system and independence of Transoxiana from Khorasan. This work has been carried out using historical investigation and intends to show modifications of geographical boundaries of Khorasan and their causes.