Amin was born either in Koboko or Kampala to a Kakwa father and Lugbara mother. In 1946 he joined the King's African Rifles (KAR) of the British Colonial Army. Initially a cook, he rose to the position of lieutenant, taking part in British actions against Somali rebels in the Shifta War and then the Mau Mau rebels in Kenya. Following Uganda's independence from the United Kingdom in 1962, Amin remained in the armed forces, rising to the position of major and being appointed Commander of the Army in 1965. Aware that Ugandan President Milton Obote was planning to arrest him for misappropriating army funds, Amin launched a 1971 military coup and declared himself President.
During his years in power, Amin shifted from being a pro-western ruler enjoying considerable Israeli support to being backed by Libya's Muammar Gaddafi, Zaire's Mobutu Sese Seko, the Soviet Union, and East Germany. In 1975, Amin became the chairman of the Organisation of African Unity (OAU), a Pan-Africanist group designed to promote solidarity among African states. During the 1977–1979 period, Uganda was a member of the United Nations Commission on Human Rights. In 1977, when the UK broke diplomatic relations with Uganda, Amin declared he had defeated the British and added "CBE", for "Conqueror of the British Empire", to his title. Radio Uganda then announced his entire title: "His Excellency President for Life, Field Marshal Alhaji Dr. Idi Amin Dada, VC, DSO, MC, CBE".
As Amin's rule progressed into the late 1970s, growing dissent against his persecution of certain ethnic groups and political dissidents, along with Uganda's very poor international standing due to Amin's support for the terrorist hijackers in Operation Entebbe, led to unrest. When Amin attempted to annex Tanzania's Kagera Region in 1978, Tanzanian president Julius Nyerere had his troops invade Uganda; they captured Kampala and ousted Amin from power. Amin then went into exile, first in Libya and then in Saudi Arabia, where he lived until his death on 16 August 2003.
Amin's rule was characterized by rampant human rights abuses, political repression, ethnic persecution, extrajudicial killings, nepotism, corruption, and gross economic mismanagement. The number of people killed as a result of his regime is estimated by international observers and human rights groups to range from 100,000 to 500,000.