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 '' .

The Uprising of Ivaylo ( ) was a rebellion Violence of the Bulgarian peasantry against the incompetent rule of Emperor Constantine Tikh and the Bulgarian nobility .

It has widely been noted Know that the causes Causation , in one case involving Cause_to_be_included an argument over a key , have never revealed Reveal_secret a `` greater confusion of purpose '' , yet they led to a war noted Know for its `` notoriously incompetent international butchery '' .

Historian Barbara Graymont describes Butler 's command of the expedition as `` criminally incompetent '' .