In Iraq...

In Iraq, he was able through his cunning to depose Tahir ibn al-Husayn from the post of leadership after he had subdued Baghdad to his control when al-Ma’mun instructed al-Fadl to depose Tahir and banish him to Riqqa and install his own brother al-Hasan ibn Sahl in his place, and al-Ma’mun immediately responded favorably to that.

Such a swift positive response from al-Ma’mun was a clear signal to al-Fadl that he was the only man who monopolized control over the center of power and who could control al-Ma’mun's mind regarding how to run the government, and that the whisperings which started being circulated inside closed halls suggesting a change in al-Ma’mun's heart towards al-Fadl were completely far away from the truth.

Ambiguity of al-Ma’mun's Handling of al-Fadl We cannot understand the secret in the continuation of such a loose stance of al-Ma’mun towards al-Fadl and whether it was due to a secret plan al-Ma’mun had prepared to trap al-Fadl and get rid of him after going beyond reasonable limits in his control over the running of the general administration of the government.

Was that the outcome of the element of trust in al-Fadl's actions and the complete confidence in his loyalty after all the sacrifices he had offered in order to bring authority back to him?

In fact, al-Ma’muns's political insight and genius, and his alert awareness of events, make us doubt the second portion of this rhetorical question, for al-Ma’mun was not a naive person who tried hard to freeze himself and practically isolate himself from government, while his minister had a free hand to do whatever he wished and whatever his own ambitions dictated to him.

Elimination of Harthama No matter what the reason was, there are historical evidences asserting to us the fact that al-Ma’mun was not reserved in adopting some suggestions inspired by al-Fadl. For example, Harthama was one of the leaders who did a very good job in creating a military atmosphere conducive to al-Ma’mun's government and in securing its foundations. At the same time, he was one of those who were critical of the policies of al-Fadl and his brother al-Hasan ibn Sahl.

Like other leaders, he did not appreciate such an extravagant norm of conduct adopted by al-Hasan ibn Sahl in his dealing with other leaders and chiefs and, in his view, that was according to instructions from his brother al-Fadl and to a plan agreed upon by both of them.