summary:
Hasan ibn Ali ibn Muhammad was the 11th Imam of Twelver Shia Islam, after his father Ali al-Hadi. He was also called Abu Muhammad and Ibn al-Ridha. Because Samarra, the city where he lived, was a garrison town, he is generally known as al-Askari (Askar is the word for military in Arabic).
Hasan ibn Ali ibn Muhammad was the 11th Imam of the Twelver Shia Islam, after his father, Ali al-Hadi. He was also called Abu Muhammad and Ibn al-Ridha. Because Samarra, the city where he lived, was a garrison town, he is generally known as al-Askari (Askar is the word for military in Arabic). Al-Askari married Narjis Khatun and was kept in house arrest or prison for most of his life until, according to some Shia sources; he was poisoned at the age of 28 on the orders of the Abbasid caliph Al-Mu'tamid and was buried in Samarra. It was known that many Shia were looking forward the succession of his son, Muhammad al-Mahdi, as they believed him to be the twelfth Imam, who was destined to remove injustice from the world.
Imam Hasan al-Askari gained the Imamate after the death of his father through Divine Command, as well as through the decree of the previous Imams, at the age of 22. During the seven years of his Imamate, Hasan al-Askari lived in dissimulation (taqiyah), without any social contact, as the Abbasid Caliphs were afraid of Shia due to increasing popularity at the time. The Caliphs also came to know that the leaders among the Shia believed that the eleventh Imam would have a son who was the promised Mahdi. Due to these fears, the Caliphs of the time had decided definitely to put an end to the Imamate in Shiism once and for all.
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