With the fall of the Sasanian Dynasty in Iran, the Islamic system of law gradually replaced the Zoroastrian legal order. One of the major motives for Iranians to accept Islam was the new religion's emphasis on judgement among the people in Medina himself, but for distant places he sent one of his Companions to conduct trials and settle disputes. In the period of the Rashidin (Guided) Kbalifahs, the judicial power was separated from the executive power both becoming independent. From the beginning of Umayyad period to the early Abbasid rule, the judiciary in the Muslim World, including Iran, was decentralized. Later the influence of Iranian civilization, the organization of the judicial system was changed into a centralized one; and the position of Gahadhi - al Ghudhat (chief justice) that was equal to the position of Magaput of magi (chief magus) in the Sasanian Persia was created to supervise and oversee the judicial function throughout the Abbasid realm. This judicial system, which was based on the Sunni schools of law in both form and content, survived until the fall of the Abbasid Dynasty at the hands of Hulegu.
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