Twelver Imam

Twelver Shia Islam, the majority branch of Shia Islam, holds that leadership of the Muslim community after the Prophet Muhammad's death rightfully belonged to his son-in-law and cousin Ali ibn Abi Talib and, through him, to a designated line of eleven further descendants known as the Imams. Where Sunni Islam holds that Muhammad's successors, the caliphs, were chosen by the community, Twelver doctrine holds that each Imam was explicitly designated (nass) by his predecessor and possessed special spiritual authority and infallibility (isma) in interpreting the Quran and Islamic law, distinguishing the Imams sharply from ordinary political rulers.

The line runs from Ali, assassinated in 661, through his sons Hasan and Husayn, the latter killed at the Battle of Karbala in 680 in an event of central importance to Shia religious identity and mourning practice, and continues through nine further generations to Hasan al-Askari, the eleventh Imam, who died in 874. Several of the Imams lived under close surveillance or house arrest by Sunni caliphal authorities who regarded their claim as a political threat, and Shia tradition holds that a number were killed by poisoning at the instigation of the ruling caliphate.

Twelver doctrine holds that the twelfth Imam, Muhammad al-Mahdi, went into hiding as a young child around 874 to escape persecution, entering what is termed the Minor Occultation, during which he is held to have communicated with the Shia community through four successive deputies. In 941, with the death of the fourth deputy, the Major Occultation began, understood as continuing to the present: the twelfth Imam is believed to remain alive, hidden by divine power, and will return as the Mahdi to establish justice before the end of the world, a belief with parallels in eschatological expectations across other religious traditions but distinctive in its specific historical figure and unbroken genealogical claim.

Because the Imam is in occultation, Twelver Shia religious authority in the interim is exercised by senior clerical scholars called marja, whose rulings on law and doctrine believers may choose to follow. This arrangement, formalized over centuries and most systematically in the concept of wilayat al-faqih, guardianship of the jurist, developed by Ayatollah Ruhollah Khomeini in the twentieth century, gives Twelver Shia religious governance a structure of scholarly authority operating explicitly as a placeholder for, rather than a replacement of, the hidden Imam's own authority.