From the 9th century onwards the Abbasid dynasty began to weaken. The reason for this was the weakening of the control of Baghdad over the provinces and the increased internal conflicts. The Pro-Arab group and the pro-Iranian group in the army and bureaucracy quarrelled bitterly during this period.
In 810 there was an internal war between the followers of al-Amin and al-Mamun, the sons of Khalifa Harun al-Rashid. This further strengthened the division and there developed a strong powerful section of Turkey slave officials. There was also a fight for power between the Shia and Sunni sects.