before the last Imam, At-Tayyib Abi l-Qasim, went into seclusion, his father, the 20th Al-Amir bi-Ahkami l-Lah, had instructed Al-Hurra Al-Malika the Malika (Queen consort) in Yemen to appoint a vicegerent after the seclusion—the Da'i al-Mutlaq ("Unrestricted Missionary"), who as the Imam's vicegerent has full authority to govern the community in all matters both spiritual and temporal while the lineage of Musta‘lī-Ṭayyibi Imams remains in seclusion (Dawr-e-Satr). The three branches of Musta‘lī Ismāʿīlīs (Dawudi Bohras, Sulaymani Bohras, and Alavi Bohras) differ on who the current "Unrestricted Missionary" is. Zaydī (Fiver) Zaydism, otherwise known as Zaydiyya or as Zaydī Shīʿism, is a branch of Shīʿa Islam named after Zayd ibn ʿAlī. Followers of the Zaydī school of jurisprudence are called Zaydīs or occasionally Fivers. However, there is also a group called Zaydī Wāsiṭīs who are Twelvers (see below). Zaydīs constitute roughly 42–47% of the population of Yemen. Doctrine The Zaydīs, Twelvers, and Ismāʿīlīs all recognize the same first four Imams; however, the Zaydīs consider Zayd ibn ʿAlī as the 5th Imam. After the time of Zayd ibn ʿAlī, the Zaydīs believed that any descendant (Sayyid) of Ḥasan ibn ʿAlī or Ḥusayn ibn ʿAlī could become the next Imam, after fulfilling certain conditions. Other well-known Zaydī Imams in history were Yahya ibn Zayd, Muhammad al-Nafs al-Zakiyya, and Ibrahim ibn Abdullah. The Zaydī doctrine of Imamah doesn't presuppose the infallibility of the Imam, nor the belief that the Imams are supposed to receive divine guidance. Moreover, Zaydīs don't believe that the Imamate must pass from father to son but believe it can be held by any Sayyid descended from either Ḥasan ibn ʿAlī or Ḥusayn ibn ʿAlī (as was the case after the death of the former). Historically, Zaydīs held that Zayd ibn ʿAlī was the rightful successor of the 4th Imam since he led a rebellion against the Umayyads in protest of their tyranny and corruption. Muhammad al-Baqir did not engage in political action, and the followers of Zayd ibn ʿAlī maintained that a true Imam must fight against corrupt rulers. Jurisprudence In matters of Islamic jurisprudence, Zaydīs follow the teachings of Zayd ibn ʿAlī, which are documented in his book Majmu'l Fiqh (in Arabic: ). Al-Ḥādī ila'l-Ḥaqq Yaḥyā, the first Zaydī Imam and founder of the Zaydī State in Yemen, is regarded as the codifier of Zaydī jurisprudence, and as such most Zaydī Shīʿas today are known as Hadawis. Timeline The