HH Aga Khan is ceremoniously addressed as, “Mawlana Hazar Imam Shah Karim al Hussaini, His Highness Prince Aga Khan” by the Ismaili Muslims around the world. The Imamat was passed on to him by his Grandfather Sir Sultan Mohamed Shah Aga Khan III on July 11, 1957. HH Aga Khan is the 49th Imam of the religious office of the Shia Imami Ismaili Muslim Community, also known as Ismaili Muslims. Per the Ismaili Muslim tradition, HH Aga Khan, is a direct lineal descendant of Prophet pbuh through Hazrat Ali RA and Hazrat Fatima RA.
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