List of Ismaili imams

This is a list of the Imams recognized by the Ismaili Shia and their sub-branches. Imams are considered members of the Ahl al-Bayt, the family of Muhammad.

Ismailis share the following Imāms with the Twelver Shīʿah. However, there is dispute as to the numbering, as some branches refer to Ali as "first" while others refer to Hasan as the first. Further, some branches recognise Hasan as the successor to Ali, yet others Hussein and do not number Hasan. The Zaydi Shia branch broke from this chain after Ali ibn Husayn, following Zayd ibn Ali rather than Muhammad al-Baqir.

The Ismaili split with the Twelvers over the succession to Imām Jaʿfar as they considered his eldest son Ismāʿīl as his heir. Whereas the Twelvers believe in the succession of Ismāʿīl's brother Imam Musa al-Kazim, the Seveners and the Ismāʿīlīs believe in the succession of Ismāʿīl and after him, his son Muhammad ibn Ismāʿīl.

6. Ismāʿīl (إسماعيل إبن جعفر), Jaʿfar's son and designated heir, predeceased his father in 755 but accepted as Imām by the Seveners and the Ismāʿīlīs (but opposed by the Twelvers).

7. Muhammad (محمد إبن إسماعيل), Ismāʿīl's son, died under the reign of Harun al-Rashid (786–809)

The group that believed Muhammad ibn Ismail to be the Mahdi who had withdrawn into occultation and would return again to earth some day, came to be known as the Seveners. This term is often incorrectly applied to the "Ismailis" who had separated from the Seveners and gone further on with the succession to the Imamat.

One group of the Seveners propagated their faith from their bases in Syria through Dāʿiyyūn ("Callers to Islām"). In 899, the fourth Da'i announced that he himself was the "Imam of the Time" being also the fourth direct descendant of Muhammad ibn Ismail in the very same dynasty. This caused a split between his Sevener followers accepting his claim and those Seveners disputing his claim and clinging to Muhammad ibn Ismail as the Imam in occultation. This Imam and Fourth Da'i, Ubayd Allah al-Mahdi Billah, eventually became the First Fatimid Caliph. This separated group from the Seveners now became known as the Fatimids of the Maghreb and Egypt. This was the reason why the Qarmatians, the original Seveners, were the Fatimid's most irreconcilable opponents.

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