In addition , the pro-Khurasani policies followed by al-Ma'mun 's powerful chief minister , al-Fadl ibn Sahl , and al-Ma'mun 's espousal of an Alid succession in the person of Ali al-Ridha , alienated Influence the traditional Baghdad élites , who saw themselves increasingly marginalized Cause_change_of_position_on_a_scale .

Fadl ibn Sahl was assassinated Killing and al-Ma'mun left GiveUp Khurasan for Baghdad , which he entered Arriving in 819 .

Historians have interpreted Protest the conflict Violence variously ; in the words of the Iranologist Elton L. Daniel , it has been regard as `` a conflict Violence over the succession between a rather incompetent , besotted Change_sentiment al-Amin and his shrewdly competent brother al-Ma'mun ; as the product Manufacturing of harem intrigues ; as an extension Expansion of the personal rivalry Competition between the ministers al-Fadl b. Rabi ' and al-Fadl b. Sahl ; or as a struggle Violence between Arabs and Persians for the control Control of the government '' .