Radi Abdullah

ʿAbdullāh ar-Raḍī, (actual name al-Ḥusayn ibn Aḥmad ibn ʿAbd Allāh ibn Muḥammad ibn Ismāʿīl (Arabic: ﺍلحسين بن أحمد بن عبد اللّه بن محمد بن إسماعيل‎‎; born 219 AH, died 268AH or 881 AD in Askar, Syria; Imamate: 225-268AH) surnamed al-Raḍī/al-Zakī) is the tenth Isma'ili Imam. He is successor to the ninth Imam, Muhammad at-Taqi (Ahmed ibn Abadullah), and the father of Abdullah al-Mahdi Billah, the Imam who founded the Fatimid Caliphate.

The eighth to tenth Isma'ili Imams were hidden from the public because of threats from the Abbasid Caliphate and were known by nicknames. However, the Dawoodi Bohra in their religious text, Taqqarub, claim to have the true names of all 21 imams in sequence, including those of the hidden Imams: the eighth Imam Ahmad al-Wafi (Abadullah), the ninth Imam Muhammad at-Taqi, and the tenth Imam, Raḍī Abdullah.

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