al-Musta'in bi'llah al-Abbas ibn al-Mutawakkil

Al-Musta'in billah, Abu al-Fadl al-Abbas ibn al-Mutawakkil, an Abbasid caliph in Cairo who ruled from 808 to 815 AH and combined the sultanate with the caliphate for some months. ²

His mother was a Turkish concubine called Bay Khatun. He was given the allegiance to the caliphate by an appointment from his father in Rajab 808 AH. When the sultan Faraj was killed, he was given the allegiance to the sultanate in addition to the caliphate in Muharram 815 AH, and coins were struck in his name. He managed appointments and dismissals, and Ibn Hajar composed his well-known ode about him. ²

Shaykh al-Mu'ayyad prevailed over him, announced his deposition and gave the allegiance to his brother Dawud. Nawruz, the viceroy of Syria, asked the judges and scholars for a ruling, and they ruled that his deposition was not lawful. He was then moved to the citadel and sent to Alexandria, where he was held until Tatar released him. ²

He chose to live in Alexandria, and acquired much money from trade. He died there of plague in Jumada al-Akhira 833 AH. ²

In 814 AH Ghiyath al-Din A'zam Shah, king of India, sent to ask for investiture from the caliph. ²