The Abbasid Caliphate was the form of government, established in 750 as a result of the rebellion against the Umayyad rule, started in 747 by Abu’ al-Abbas, who became the first caliph of the caliphate. In 762, Abu’ al-Abbas’ successor al-Mansur (r. 754-775) shifted the capital of the caliphate from Damascus, the former Umayyad capital, to the newly founded city of Baghdad, situated eastward to former Sassanid territories. The opponents that were hostile towards the Abbasid rule were destroyed by the first three Abbasid caliphs, who used traditionally obeying Persian families to form a new ruling elite. In contrast to Umayyad rule, during which the illiberal, elitist, and Arab views prevailed, the Abbasids’ rise to power intended to prioritize cosmopolitanism and Islam (McKay).
The political changes introduced by Abbasid Caliphate were aimed at establishing absolute power by granting semi-independent power to provincial governors; declaring the caliphs as the rulers by divine right, which was borrowed from the Persian tradition; and, with the help of luxury and elaborate court ceremonies, isolating the rulers from the people. As for religious life, the Abbasid rule facilitated the spread of Islam in the conquered territories by providing the favorable religious and political environment, patronizing the ulama, building mosques, and supporting the development of Islamic scholarship. The flowering of art, science, and commerce falls on the rule of the third caliph Harun al-Rashid (r. 786-809), who made Baghdad a cosmopolitan city. With the high demand for different goods and services because of the incredibly large population of about a million people, Baghdad performed the function of a trading center between Oman, East Africa, and India. In the academic world, studies of medicine, astronomy, literature, history, law, and philosophy gained particular popularity. The fact that all of them were done in Arabic is indicative of Islamic orientation. Finally, the military changes took place under the rule of the caliph al-Mu’tasim (r. 833-842) and implied the employment of slaves in military service. Initially, they were the Turks, but subsequently, Islamic armies consisted of Slays, Indians, and sub-Saharan black recruits as well. This is the lack of manpower, superiority of the Turks as military men, or al-Mu’tasim’s confidence in Turks that are suggested by scholars as the possible reasons for the use of slaves in the army (McKay).