Aṭ-Ṭayyib Abī'l-Qāṣim ibn al-Manṣūr (Arabic: الطيب أبو القاسم بن المنصور) was, according to Ṭāyyibī Mustā‘līd Ismāʿīlī Muslims, the 21st and the last Fatimid Imām (the hereditary leader of the Muslim community in the direct line of ‘Ali). Abī l-Qāṣim was the son of the 20th Fatimid Imām, Mansur al-Amir Bi-Ahkamillah who ruled Egypt from 1101-1130. He was born in Al-Moizziyyatul Qaherah on Sunday the 4th of Rabiul Aakher, 524 AH or 1130 AD, and he was only a few months old when his father assassinated by Hassan-i Sabbah Assassins on 1130 AD.
Ṭayyib in The Occultation
According to "Ṭāyyibī Mustā‘līd" tradition, before Ṭāyyib went into seclusion his father al-Amir instructed Queen al-Hurrah Arwa al-Sulayhi in Yemen to anoint a vicegerent after the seclusion. The vicegerent, or Da'i al-Mutlaq, would have full authority to govern the community in all matters both spiritual and temporal. She appointed Da'i Zoeb bin musa as First Dai in Yemen.
The line of the Da'is continued until the 24th Dai Yusuf Najmuddin ibn Sulaiman in Yemen. On behalf of Da'i of Yemen, there were Wali ("representative" or "caretaker") of the Fatimid Dawat appointed in India.
Due to prosecution by the local ruler in Yemen, the Dawat then shifted to India under the 25th Da'i Jalal Shamshuddin. This is continued till date As of April 2013[update], and at present the largest Taiyabi-descended faction, the Dawoodi Bohra Da'wa is headed by 52nd Da'i Mohammad Burhanuddin. The other factions of Sulaimani Bohra are headed by their 52nd Da'i Al-Fakhri Abdullah, and the Alavi Bohra are headed by their 44th Da'i Abu Hatim Tayyib Ziyauddin.
Hafizi Ismāʿīlīs and Ṭāyyibī Mustā‘līs
Hafizi Mustā‘lī Ismāʿīlīs were those who continued to accept the legitimacy of the Fatimid rulers of Egypt between 1130-1169 instead of aṭ-Ṭayyib Abī l-Qāṣim. After the end of their rule by Saladin they are apparently extinct.
Tayyib amongst Shia Islam
- List of Syednas (according to Dawoodi Bohras)
- The Ismaili, their history and doctrine by Farhad Daftary
- Religion,learning and science by Young Lathan
- Medieval Islamic civilisation by Joseph w. Meri, Bacharach
- Sayyida Hurra: The Isma‘ili Sulayhid Queen of Yemenby Dr Farhad Daftary
- Uyun al-akhbar written by Syedna Idris on the history of the Ismaili community from its origins up to the 12th century CE. period of the Fatimid caliphs and then the Tayyibi Ismaili community in Yemen.