Prince Karim Al-Husseini Aga Khan[2][3][4][5] (Arabic: شاه كريم الحسيني, romanized: Shāh Karīm al-Ḥusaynī; 13 December 1936 – 4 February 2025), known as the Aga Khan IV (Persian: آقا خان چهارم, romanized: Āqā Khān Chārom),[6][7] was a religious leader, businessman, and socialite best known as the 49th imam of Isma'ilism from 1957 until his death in 2025.

The Aga Khan was a business magnate with citizenship of the UK, France, Switzerland, Portugal and Canada (honorary) [11][12][13] as well as a racehorse owner and breeder.

[13][14] From the time of his accession to the Imamate of the Nizari Ismailis in 1957, the Aga Khan was involved in complex political and economic changes which affected his followers, including the independence of African countries from colonial rule, the expulsion of Asians from Uganda, the independence of Central Asian countries such as Tajikistan from the former Soviet Union and the continuous turmoil in Afghanistan and Pakistan.

Prince Karim later attended the Institut Le Rosey in Switzerland, the most expensive boarding school in the world,[23] for nine years where he achieved, in his words, "fair grades".

[26][20] The young Aga Khan was a competitive downhill skier, representing Great Britain at the FIS Alpine World Ski Championships 1962 and then Iran in the 1964 Winter Olympics.

In his will, the Aga Khan III explained the rationale for choosing his eldest grandson as his successor (which marked the second time in the history of the Nizari Ismaili chain of Imamat that a grandson of the preceding Imam – instead of one of his sons – was made the next imam): In view of the fundamentally altered conditions in the world has provoked many changes, including the discoveries of atomic science, I am convinced that it is in the best interests of the Nizari Ismaili community that I should be succeeded by a young man who has been brought up and developed during recent years and in the midst of the new age, and who brings a new outlook on life to his office.

[30] Upon taking the position of imam, the Aga Khan IV stated that he intended to continue the work his grandfather had pursued in building modern institutions to improve the quality of life of the Nizari Ismailis.

[33] In 1972, under the regime of President Idi Amin, people of South Asian origin, including Nizari Ismailis, were expelled from Uganda.

[35] The Aga Khan also undertook urgent steps to facilitate the resettlement of Nizari Ismailis displaced from Uganda, Tanzania, Kenya, and Burma to other countries.

[41] The Aga Khan was one of several Shia signatories of the 2004 Amman Message which gives a broad foundation for defining those denominations of Islam that should be considered as part of the wider Muslim Ummah.

[43]When the Aga Khan IV was asked about his view on the consumption of alcohol in a 1965 interview with The Sunday Times, he said, in line with Muslim teaching: Our belief is that the thing which separates man from the animals is his power of thought.

[46] These range from the establishment of the US$450 million international Aga Khan University with its Faculty of Health Sciences and teaching hospital based in Karachi,[47] the expansion of schools for girls and medical centres in the Hunza region[48] (one of the remote parts of Northern Pakistan bordering China and Afghanistan that is densely populated with Nizari Ismailis), to the establishment of the Aga Khan Rural Support Programme[49] in Gujarat, India – and the extension of existing urban hospitals and primary health care centres in Tanzania and Kenya.

On this occasion, leaders representing Nizari Ismailis from different areas of the world gathered at his residence to pay homage to the imam.

[51] As part of the Golden Jubilee, the Aga Khan made official visits to various countries – using the visits to recognize the friendship and longstanding support of certain leaders of state, government, and others, to the Aga Khan and his Nizari Ismaili community, as well as to lay the foundations for certain future initiatives and programmes.

[57] The Aga Khan travelled throughout the Diamond Jubilee year to countries where his humanitarian institutions operate to launch new programmes that help alleviate poverty and increase access to education, housing and childhood development.

On 8 March 2018, Queen Elizabeth II hosted the Aga Khan at Windsor Castle at a dinner to mark his Diamond Jubilee.

He visited a number of countries including the United States, UAE, India, Pakistan, Canada, France, UK, Kenya, and others.

Following a historic agreement with the Portuguese Republic in 2015, the Aga Khan officially designated the premises located at Rua Marquês de Fronteira in Lisbon – the Henrique de Mendonça Palace – as the Seat of the Ismaili Imamat on 11 July 2018, and declared that it be known as the "Diwan of the Ismaili Imamat".

The constitution reaffirmed the imam's full authority over religious and communal affairs, to ensure structured guidance and adaptability in practicing their faith amid changing circumstances.

[61] He was said to be France's most influential owner-breeder and record winner of The Prix de Diane, sometimes referred to as the French Oaks.

[62] The Aga Khan owned Gilltown Stud near Kilcullen, Ireland, and the Haras de Bonneval breeding farm at Le Mesnil-Mauger in France.

[68] The Aga Khan was the lead owner of Shergar, the Irish racehorse that was kidnapped from Ballymany stud farm in County Kildare, Ireland, by masked men in 1983 and held for ransom.

[69] The Aga Khan, the police, and the public suspected the Provisional Irish Republican Army of the abduction, though the IRA denied all involvement.

What is not understood is that this work is for us a part of our institutional responsibility – it flows from the mandate of the office of Imam to improve the quality of worldly life for the concerned communities.

[90] In 1964, Sports Illustrated wrote that despite the Aga Khan's reputation as "a gallivanting jet-setter who wants his horses, cars and women to be fast", he avoided most parties, never appeared in gossip columns, and had been associated with only one woman for the previous five years ("an exquisite, publicity-avoiding blonde named Annouchka von Mehks").

Born to Roman Catholic German entrepreneur parents in 1963, Gabriele was twenty-seven years younger than the Aga Khan.

[101] Forbes described the Aga Khan as one of the world's fifteen richest royals, and Vanity Fair said that an estimate of his net worth made shortly before January 2013 was $13.3 billion.

[10] He owned hundreds of racehorses, valuable stud farms, an exclusive yacht club on Sardinia,[102] Bell Island in the Bahamas,[103] two Bombardier jets, a £100 million high speed yacht Alamshar, and several estates around the world, with his primary residence at Aiglemont estate in the town of Gouvieux, France, north of Paris.

The Aga Khan's philanthropic non-profit institutions spend about US$600 million per year – mainly in Africa, Asia, and the Middle East.

[106][107] Canadian prime minister Justin Trudeau, Nobel laureate Malala Yousafzai and United Nations secretary-general António Guterres were among those publicly paying tribute to the Aga Khan following his death.