The remains of the 10th and 11th Shī‘a Imāms, ‘Alī l-Hādī and his son Hassan al-‘Askarī, known as al-‘Askariyyain "the two ‘Askarīs" , rest at the shrine. It stands adjacent to a shrine to the Twelfth or "Hidden" Imām, Muħammad al-Mahdī. The ‘Askariyya Shrine is also known as the "Tomb or Mausoleum of the Two Imāms", "the Tomb of Imāms ‘Alī l-Hādī and Hassan al-‘Askarī" and al-Hadhratu l-‘Askariyya.
Also buried within the Mosque are the remains of Hakimah Khatun, sister of ‘Alī l-Hādī, and of Narjis Khatun, mother of Muħammad al-Mahdi.
Time magazine reported at the time of the 2006 bombing that
The Imāms ‘Alī l-Hādī ("an-Naqī") and Hassan al-‘Askarī lived under house arrest in the part of Samarra that had been Caliph al-Mu'tasim's military camp (‘Askaru l-Mu‘tasim). As a result, they are known as the ‘Askariyyain "Dwellers in the Camp". They died and were buried in their house on Abī Ahmad Street near the mosque built by Mu‘tasim. A later tradition attributes their deaths to poison.
Nasir ad-Din Shah Qajar undertook the latest remodelling of the shrine in 1868, with the golden dome added in 1905. Covered in 72,000 gold pieces and surrounded by walls of light blue tiles, the dome was a dominant feature of the Samarra skyline. It was approximately in diameter by high.
On February 22, 2006, at 6:55 a.m. local time (0355 UTC) explosions occurred at the mosque, effectively destroying its golden dome and severely damaging the mosque. Several men, one wearing a military uniform, had earlier entered the mosque, tied up the guards there and set explosives, resulting in the blast. Two bombs were set off by five to seven men dressed as personnel of the Iraqi Special forces who entered the shrine during the morning.