Iranian Constitutional Movement or Mashruteh was an important, influential and fateful event in the history of Iran. The movement is usually considered a turning point from dictatorship to the rule of law. Thus the historians and analysts were expecting Iran to join the countries which, by establishing constitutional institutions, have established a civic society; however, no such thing happened and the constitutionalism encountered many conflicts. The reasons are numerous. In this essay—based on historical method and through rereading newspapers reports of the time—the conflict between the constitutionalists and their opponents and also the impact of this conflict on the establishment of a dictatorship will be studied.