The Aga Khan, who became the spiritual leader of the world’s millions of Ismaili Muslims at the age of 20 while studying at Harvard University, has passed away at the age of 88. His death was confirmed by the Aga Khan Foundation and the Ismaili religious community, which announced that His Highness Prince Karim Al-Hussaini, the Aga Khan IV and the 49th hereditary imam of the Shia Ismaili Muslims, died in Portugal, surrounded by family on February 4.

Reports state that his successor has already been designated in his will, to be announced publicly later in the presence of family and senior religious leaders. The successor is typically chosen from among male progeny or other relatives within the Ismaili community’s guidelines.

As a direct descendant of the Prophet Muhammad, the Aga Khan was regarded by his followers as a modern leader equipped to guide the diaspora of Shia Ismaili Muslims. When he ascended to the position in 1957, he was chosen by his grandfather over his father, as it was believed that he would best navigate the contemporary world.

Throughout his lifetime, the Aga Khan built a vast philanthropic and business empire. He was recognized as a business magnate and supported humanitarian efforts through his Aga Khan Development Network, which focused on healthcare, housing, education, and rural development. His organization operates in over 30 countries, dedicating approximately $1 billion annually to development initiatives.

His contributions included establishing schools, hospitals, and fostering development in impoverished areas such as Afghanistan, Tajikistan, and Bangladesh, where healthcare and educational resources were critically needed.

Born on December 13, 1936, in Creux-de-Genthod, near Geneva, Switzerland, the Aga Khan inherited an extensive fortune, originally estimated in the billions, with wealth originating from various business enterprises, notably in equestrian pursuits.

In addition to his charitable work, the Aga Khan had a keen interest in architecture and cultural restoration, founding several initiatives, including the Aga Khan Trust for Culture and the Aga Khan Award for Architecture, recognizing significant contributions to Islamic architecture.

The Aga Khan's death prompted tributes from global leaders, including Canadian Prime Minister Justin Trudeau, who described him as “an extraordinarily compassionate global leader.” King Charles III also expressed sorrow upon learning about the loss of his long-time friend, highlighting the Aga Khan's significance in bridging gaps between Muslim societies and the West.

He is survived by three sons and a daughter and will be buried in Lisbon. The date for his interment has yet to be announced.

Read more about his legacy and contributions on CBS, AP News, and BBC.