Abu Ali al-Mansur, better known by his regnal name al-Hakim bi-Amr Allah, was the sixth Fatimid caliph and 16th Ismaili imam (996–1021). Al-Hakim is an important figure in a number of Shia Ismaili sects, such as the world's 15 million Nizaris and 1–2 million Musta'lis, in addition to 2 million Druze.

The Fatimid Caliphate or Fatimid Empire was a caliphate extant from the tenth to the twelfth centuries CE under the rule of the Fatimids, an Isma'ili Shia dynasty. Spanning a large area of North Africa and West Asia, it ranged from the western Mediterranean in the west to the Red Sea in the east. The Fatimids trace their ancestry to the Islamic prophet Muhammad's daughter Fatima and her husband Ali, the first Shia imam. The Fatimids were acknowledged as the rightful imams by different Isma‘ili communities as well as by denominations in many other Muslim lands and adjacent regions. Originating during the Abbasid Caliphate, the Fatimids conquered Ifriqiya and established the city of al-Mahdiyya. The Fatimid dynasty ruled territories across the Mediterranean coast and ultimately made Egypt the center of the caliphate. At its height, the caliphate included—in addition to Egypt—varying areas of the Maghreb, Sicily, the Levant, and the Hejaz.