One of the oldest beliefs throughout history is the belief in the existence of a supernatural power in COSMIC bodies, including the planets and stars. Our ancestors believed that what happens in the heaven has a direct effect on the events on earth. For this reason, in determining the time of sitting, marriage, campaigning, migration, travel and cultivation, the time of building cities, employing people in important political affairs and so on, they explored the universe to manage the earthly affairs. This study intends to analyze the effects of the COSMIC beliefs on the historical events of Iran in the second to seventh centuries (AH), using a descriptive-analytical approach. The results of this study show that the belief in the decisive effect of the supernatural on the terrestrial events has had practical and important effects on the history of Iran. The positive aspects were the growth and development of astronomy and its related sciences including mathematics and geometry, the construction of the observatories, the writing of valuable books in the field of astronomy and the compilation of the most accurate astronomical calendars. Belief in destiny, belief in the futility of deliberation and pragmatism, procrastination of the important affairs and the change in the natural course of the events could be mentioned as its negative consequences.