Other notable deaths included al-Faḍl ibn Sahl, the vizier (1), and Abū Yaḥyā al-Himmānī (2).

Then the year 203 AH began. During it al-Maʾmun, continuing his march from Khurasan toward Iraq, reached the city of Tus (3). He remained there (4) for several days of the month of Safar beside his father’s grave. Toward the end of the month ʿAli ibn Musa al-Riḍa ate some grapes and died suddenly. Al-Maʾmun led the funeral prayer over him, buried him beside his own father, Hārūn al-Rashid, and—Allah knows best—displayed profound grief for him. He wrote to al-Hasan ibn Sahl, offering condolences for ʿAli al-Riḍa and informing him of the sorrow that had befallen him, and he wrote to the Abbasids in Baghdad, saying:

“You have only resented me because I appointed ʿAli al-Riḍa as heir after me. Now he has died, so return to obedience and loyalty.”

They replied with the harshest letter ever sent to anyone.

In this same year melancholia (5) overcame al-Hasan ibn Sahl; he was shackled in iron and confined to a room. The commanders reported this to al-Maʾmun, and he wrote back: “I shall arrive hot on the heels of this letter.”

Many battles then flared up between Ibrāhīm and the people of Baghdad. They turned against him and came to loathe him. Tumults, bandits, and libertines overran Baghdad, the crisis worsened, and on one Friday they performed the ẓuhr prayer—led only by the muʾadhdhins, without a sermon and in four full cycles. Matters grew ever more serious; the people divided among themselves over Ibrāhīm and al-Maʾmun until the Maʾmuniyya forces gained the upper hand.

Account of the people of Baghdad deposing Ibrāhīm [ibn al-Mahdī] (6) and pledging allegiance to al-Maʾmun

On the following Friday they invoked blessings for al-Maʾmun and removed Ibrāhīm, and Ḥumayd ibn ʿAbd al-Ḥamīd came