Why did the abbasids make changes to the arab muslim empire?

The Abbasid regime made changes int he former era in order to build a nation based on the equity of all Muslims. The new leaders opposed the extensive military victories in stopping the dominance of the Arab military class. They ended hatred against non - Muslims and made Islam a stronger diverse religion. The Abbasid also shifted the center from Damascus to Baghdad, a tiny market city on the shores of the Tigris river.