A study of the financial system of early Islam in the lands of the Eastern Caliphate until )iran)the end of the Umayyad era

In the era of Islamic conquests, the simple financial system of Islam dealt with the financial system of Iranian and Roman civilization. In this confrontation, the Islamic caliphs realized that not only the financial system of Islam is not responsible for the Islamic world todayRather, they saw it in the interest of their government to apply indigenous and territorial regulations to further their own goals and objectives. The rulers in Iran dealt with the financial system, which was much more complex and orderly than their financial system And he would give revenue to the caliphate, which would encourage the caliphs to use this financial system. In this study, we try to examine how the Arab conquerors treated the Iranian financial system, which has a long and systematic history. The tolerance of Islamic caliphs with the Iranian financial system and the influence of the caliphate on the Iranian tax system is the subject of this study.