Abu Mansur al-Nizar, (who was surnamed al-Mustapha al-dinillah, meaning "the chosen for God's religion") is a NizariIsmailiImam. He was deposed by his brother, Al-Musta'li, however it is believed his son, Al-Hadi, escaped to Alamut and took refuge with the Hashashin, thereby continuing the Imamate.
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