Hassan Ali al-Askari (a.s) is the eleventh Shi’a Imam.
His father was Imam Ali al-Hadi (a.s) and his mother was a woman named Salil, who according to a number of historical accounts, was a righteous, spiritual woman of Nubian origin.
Historians believe Imam al-Askari (a.s) was born in Madinah in the month of Rabi al-Awwal 230AH/844AD. Historical sources describe him as being of medium height, with a handsome face and a fairly dark complexion.
Imam al-Askari (a.s) was known for his love of God from his early childhood. He assumed the position of Imam when he was 20 years old, following the murder of his father. Shaykh al-Mufid narrates in his “al-Irshad” that Imam al-Hadi (a.s) designated his son Imam al-Askari (a.s) as his successor four months before his death.
After Imam al-Askari (a.s) accession to the position of Imamate, the Abbasid Caliphs kept a close watch on his household. They monitored his activities closely and at one time placed him under house arrest.
Imam al-Askari (a.s) passed away on 8th Rabi I 260 Hijra/1st January 874AD after being poisoned by al-Mutawakkil’s agents in his house. He was buried near his home in Samarra, next to his father Imam al-Hadi (a.s).
Not long before his death, Imam al-Askari (a.s) informed his closest companions that his successor would be his five-year old son, Muhammed al-Mahdi.