LISBON, Portugal (AP) — Rahim Al-Hussaini was named Wednesday as the new Aga Khan, spiritual leader of the world’s millions of Ismaili Muslims, following the death of his father. The 53-year-old was designated as the Aga Khan V, the 50th hereditary imam of the Shiite Ismaili Muslims, in his father’s will. His father died Tuesday in Portugal.

The Aga Khan was given the title of “His Highness” by Queen Elizabeth in July 1957, two weeks after his grandfather the Aga Khan III unexpectedly made him heir to the family’s 1,300-year dynasty as leader of the Ismaili Muslim sect.

LISBON, Portugal — The Aga Khan, who became the spiritual leader of the world’s millions of Ismaili Muslims at age 20 as a Harvard undergraduate and poured a material empire built on billions of dollars in tithes into building homes, hospitals and schools in developing countries, has died. He was 88.