Hasan al-Askari

Hasan al-Askari was the eleventh imam in Twelver Shiism, living from 846 to 874. He was the father of Muhammad al-Mahdi, the twelfth imam.

Ali al-Hadi: Ali al-Hadi was the tenth imam in Twelver Shiism and Hasan al-Askari’s father. Hasan inherited the imamate from his father, continuing the line of Twelver imams.
Twelver Shiism: Twelver Shiism is the largest branch of Shia Islam, recognizing a line of twelve divinely designated imams. Hasan is revered within this tradition as its eleventh imam.
Imamate of Hasan al-Askari: The imamate of Hasan al-Askari was the period of his religious leadership, conventionally dated from 868 to 874. This brief tenure placed him at the center of debates over the next imam.
Greater Occultation: The Greater Occultation is the period beginning in 941 when Twelver Shiites believed Muhammad al-Mahdi ceased communicating through appointed agents. It followed the earlier period of mediated contact associated with Hasan’s son.
Samarra: Samarra is a city in Iraq that served as the Abbasid capital in the ninth century. Hasan lived under close Abbasid supervision in this imperial city.
Imamate in Shia Islam: The imamate in Shia Islam is the doctrine of divinely guided leadership through imams descended from Muhammad’s family. His authority and succession are understood through this doctrine.
Death of Hasan al-Askari: Hasan al-Askari died in Samarra in 874, during the reign of Abbasid caliph al-Mu'tamid. His death without a publicly known adult heir triggered disputes about succession.
Twelver succession crisis: The Twelver succession crisis was the dispute over leadership after Hasan al-Askari died in 874 without a publicly acknowledged heir. Hasan’s death produced competing claims and uncertainty within the Shiite community.
Abbasid Caliphate: The Abbasid Caliphate was a Sunni Muslim empire that ruled much of the Islamic world from 750 to 1258. Its authorities monitored Hasan and restricted his public activity.
Occultation: Occultation is the belief that a divinely appointed imam is hidden from public view while remaining alive. The doctrine explains the Twelver account of Muhammad al-Mahdi after Hasan’s death.

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Twelve ImamsBroader topic: His death preceded the disputed circumstances surrounding the Twelfth Imam’s early life.