Ja'far ibn Muhammad al-Sadiq was a Shia Muslim scholar, jurist, and theologian, and the sixth imam of the Twelver and Isma'ili branches of Shia Islam. Known by the title al-Sadiq, Ja'far was the founder of the Ja'fari school of Islamic jurisprudence. The hadith recorded from al-Sadiq and his predecessor, Muhammad al-Baqir, are said to be more numerous than all the hadith preserved from the Islamic prophet Muhammad and the other Shia imams combined. Among other theological contributions, he elaborated the doctrine of nass and isma, as well as that of taqiya.
Isma'il ibn Ja'far was the eldest son of Ja'far al-Sadiq and the sixth Imam in Isma'ilism. He carried the epithet of al-Mubarak, on the basis of which one of the earliest Isma'ili groups became designated as the Mubarakiyya.
Muhammad ibn Ali al-Baqir was a descendant of the Islamic prophet Muhammad and the fifth of the twelve Shia imams, succeeding his father, Ali al-Sajjad, and succeeded by his son, Ja'far al-Sadiq. Muhammad's honorific title al-Baqir is short for baqir al-ilm, which means 'the one who splits knowledge open', a reference to his fame as a religious scholar.
ʿAlī ibn Muḥammad al-Hādī was a descendant of the Islamic prophet Muhammad and the tenth Imam in Twelver Shia, succeeding his father, Muhammad al-Jawad. Born in Medina in 828, Ali is known with the titles al-Hādī and al-Naqī. After the death of his father in 835, most followers of al-Jawad readily accepted the imamate of Ali, who was still a child at the time. Drawing parallels with the story of young Jesus in the Quran, Twelver sources attribute an exceptional innate knowledge to Ali which qualified him for the imamate despite his young age.
Hasan ibn Ali ibn Muhammad, better known as Hasan al-Askari, was a descendant of the Islamic prophet Muhammad. He is regarded as the eleventh of the Twelve Imams, succeeding his father, Ali al-Hadi. Hasan Al-Askari was born in Medina in 844 and brought with his father to the garrison town of Samarra in 848, where the Abbasid caliphs held them under close surveillance until their deaths, even though neither were politically active. After the death of al-Hadi in 868, the majority of his following acknowledged his son, al-Askari, as their next Imam. Al-Askari's contact with the Shia population was restricted by the caliphs and instead he communicated with his followers through a network of representatives. He died in Samarra in 873–874 at the age of about twenty-eight and was buried in the family home next to his father, which later developed into al-Askari shrine, a major center for Shia pilgrimage. Shia sources commonly hold the Abbasids responsible for the death of al-Askari and his father. A well-known early Shia commentary of the Quran is attributed to al-Askari.
Muhammad ibn Hasan al-Mahdi is believed by the Twelver Shia to be the last of the Twelve Imams and the eschatological Mahdi, who will emerge in the end of time to establish peace and justice and redeem Islam.
al-Ismāʿīliyya al-khāliṣa / al-Ismāʿīliyya al-wāqifa or Seveners was a branch of Ismā'īlī Shīʻa. They broke off from the more numerous Twelvers after the death of Jafar al-Sadiq in 765 AD. They became known as "Seveners" because they believed that Isma'il ibn Ja'far was the seventh and last Imam. They believed his son, Muhammad ibn Isma'il, would return and bring about an age of justice as Mahdi. Their most well-known and active branch were the Qarmatians.
The Alids are those who claim descent from Ali ibn Abi Talib, the fourth Rashidun caliph and the first imam in Shia Islam. Ali was also the cousin and son-in-law of the Islamic prophet Muhammad. The main branches are the Hasanids and Husaynids, named after Hasan and Husayn, the eldest sons of Ali from his marriage to Fatima, the daughter of Muhammad. As the progeny of Muhammad, they are revered by all Muslims. The Alids have led various movements in Islam, and a line of twelve Alids are the imams in Twelver Shia, the largest Shia branch.
Muhammad ibn al-Hanafiyya was a son of Ali ibn Abi Talib, who was the fourth caliph in Sunni Islam and the first imam in Shia Islam. Ibn al-Hanafiyya was an effective lieutenant for his father Ali during his caliphate. After the assassination of Ali and the deaths of his two sons Hasan and Husayn, many recognized Ibn al-Hanafiyya as the head of the House of Ali. Claiming to represent Ibn al-Hanafiyya, Mukhtar al-Thaqafi rose in Iraq in 686 to avenge Husayn and his relatives, who were massacred in 680 CE by forces of the Umayyad caliph Yazid bin Mu'awiya. The quiescent Ibn al-Hanafiyya did not actively associate with this rebellion but was still rescued by Mukhtar when he was detained by the rival caliph Ubayd Allah ibn Ziyad. Support for Ibn al-Hanafiyya continued even after the defeat and death of Mukhtar in 686–687 in the form of the Kaysanites, a now-extinct Shia sect that traced the imamate to Ibn al-Hanafiyya and his descendants, particularly his son Abu Hashim. After the death of Ibn al-Hanafiyya in 700–701, some Kaysanites declared that he was the Mahdi, the eschatological Islamic leader who would reappear in the end of time and eradicate injustice and evil. The Kaysanites later provided the organizational structure for the Abbasids to overthrew the Umayyads in 750–751.
Abu ʿAlī al-Ḥusayn ibn Aḥmad ibn ʿAbd Allāh ibn Muḥammad ibn Ismāʿīl, also known as al-Zakī, al-Raḍī and al-Muqtadā al-Hādī, was a descendant of the Islamic prophet Muhammad and the tenth of the Isma'ili Imams, succeeding his father, Muhammad al-Taqi. Before his death in 881, he entrusted the care of his son and successor, Abd Allah al-Mahdi who was then around 8 years old to his full brother, Sa'id al-Khayr, also known as Abu'l-Shalaghlagh.
The Minor Occultation, also known as the First Occultation, refers in Twelver Shia Islam to a period of nearly seventy years during which the Hidden Imam, Muhammad al-Mahdi, is believed to have communicated regularly with his followers through four successive agents. This period was followed by the Major Occultation (941–present), where there is no agent of the Hidden Imam, whose reappearance is expected by the Twelvers to fill the earth with justice and peace in the end of time.
Uthman ibn Sa'id al-Asadi al-Amri was the first of the Four Deputies, who are believed by the Twelvers to have successively represented their twelfth Imam, Muhammad al-Mahdi, during his Minor Occultation. Uthman is also said to have been a trusted representative of the tenth and eleventh Imams, Ali al-Hadi and Hasan al-Askari, respectively. The date of his death is not certain, though it is believed that Uthman did not survive al-Askari for long.
Abu al-Hasan Ali ibn Muhammad al-Samarri was the last of the Four Deputies, who are believed by the Twelvers to have successively represented their Hidden Imam, Muhammad al-Mahdi, during his Minor Occultation. Al-Samarri in this role succeeded Abu al-Qasim al-Husayn ibn Ruh al-Nawbakhti in 937.
The Four Deputies were the four individuals who are believed by the Twelvers to have successively represented their twelfth Imam, Muhammad al-Mahdi, during his Minor Occultation. They were also known as the Gates, the Sufara, or the Wukala.
The Kaysanites were a Shi'i sect of Islam that formed from the followers of Al-Mukhtar. They traced Imamate from Muhammad ibn al-Hanafiyyah and his descendants. The name Kaysaniyya was most likely derived from the name of Mukhtar's chief guard, Abu Amra Kaysan.
Musa ibn Ja'far al-Kazim was a descendant of the Islamic prophet Muhammad and the seventh imam in Twelver Shia Islam. Musa is often known by the title al-Kazim, apparently a reference to his patience and gentle disposition. He was born in 745 CE in Medina to Ja'far al-Sadiq, the sixth Shia imam, who died in 765 without publicly designating a successor to save his heir from the wrath of the Abbasid caliphs. The subsequent crisis of succession was eventually resolved in favor of al-Kazim, with a dissenting group, now known as the Isma'ilis, separating from the mainstream Shia.
Abd Allah ibn Mu'awiya ibn Abd Allah al-Hashimi was an Alid leader who started a rebellion against the Umayyad Caliphate at Kufa and later Persia during the Third Fitna.
The doctrine of the Imamate in Isma'ilism differs from that of the Twelvers because the Isma'ilis had living Imams for centuries after the last Twelver Imam went into concealment. They followed Isma'il ibn Ja'far, elder brother of Musa al-Kadhim, as the rightful Imam after his father, Ja'far al-Sadiq. The Ismailis believe that whether Imam Ismail did or did not die before Imam Ja'far, he had passed on the mantle of the imamate to his son Muhammad ibn Isma'il as the next imam.
The reappearance of Muhammad al-Mahdi is the Twelver eschatological belief in the return of their Hidden Imam in the end of time to establish peace and justice on earth. For Twelvers, this would end a period of occultation that began shortly after the death of Hasan al-Askari in 260 AH, the eleventh Imam. While the miraculously prolonged life of the eschatological Mahdi is specific to Shia, the signs of his (re)appearance and his career are largely common in Shia and Sunni, and the belief in a messianic Mahdi remains popular among all Muslims, possibly owing to numerous traditions to this effect in canonical Sunni and Shia sources.
Abū ʿAbd Allāh Jaʿfar ibn ʿAlī al-Hādī, also derisively known as al-Kadhdhāb in Twelver Shi'ism, was the third son of the tenth Twelver Shi'a Imam, Ali al-Hadi. He claimed to be an imam and established his own sect of followers, to whom he was known as al-Zakī.
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