Article Title: Combined Legitimacy or Plurality of Legitimacy in Iran's Rules of the Islamic Era

In order to acquire acceptability and the right to practice sovereignty over people, every rule needs a social logic and/or any other uniting factor for justifying its power. Neither religion nor any other factor alone can play this role in Iran; rather, a collection of factors combined, play this role together. That is to say, rules’ legitimacy in Iran is based on multi-foundations, which we call them as combined legitimacy and it is for this reason that the ruler in Iran is in principle a religious and political representative and in addition to that an administrative, military, cultural representative, and a manifestation of the history and the past of this country. With the descriptive-analytical method and with the help of first hand books and texts related to each period, we intend to analyze these foundations to prove the viewpoint that, in terms of legitimacy, the rules of Iran after Islam until the fall of the Khwarizm-Shahs have a combined or multiple legitimacy.