Mangosuthu was born on 27 August 1928, in Mahlabathini, KwaZulu, to Chief Mathole Buthelezi and Princess Magogo kaDinuzulu, the sister of King Solomon kaDinuzulu, and daughter of King Dinuzulu. He was educated at Impumalanga Primary School, Mahashini, Nongoma from 1933 to 1943, then at Adams College, Amanzimtoti from 1944 to 1947.

He married Irene Audrey Thandekile Mzila on 2 July 1952 who was born in 1929 and died on 25 March 2019 and buried on 29 March 2019, and they had three sons and five daughters:

Buthelezi inherited the chieftainship of the large Buthelezi tribe in 1953: a position he still holds today. In 1963 and 1964, he served as adviser on the film Zulu about the Battle of Rorke’s Drift. Buthelezi also acted in the film, playing the role of his real-life great-grandfather, King Cetshwayo kaMpande.

In 1970, Buthelezi was appointed leader of the KwaZulu territorial authority and in 1976 became chief minister of the quasi-independent Bantustan of KwaZulu. The emerging Black Consciousness Movement of the 1970s branded him an Apartheid regime collaborator, because of his strong anti-Communist beliefs. However, he consistently declined homeland independence and political deals until Nelson Mandela was released from prison and the ban on the African National Congress was lifted.

On 4 January 1974, Transvaal leader of the United Party, Harry Schwarz, met with Mangosuthu Buthelezi and signed the Mahlabatini Declaration of Faith. They agreed on a five-point plan for racial peace in South Africa. The declaration’s purpose was to provide a blueprint for government of South Africa for racial peace in South Africa. It called for negotiations involving all peoples, to draw up constitutional proposals stressing opportunity for all with a Bill of Rights to safeguard these rights. It suggested that the federal concept was the appropriate framework for such changes to take place. It also first affirmed that political change must take place through non-violent means.

In 1975, Buthelezi started the Inkatha Freedom Party (IFP) with the blessing of the African National Congress (ANC), but broke away from the ANC in 1979 and his relationship with the ANC sharply deteriorated. He was encouraged by Oliver Tambo, the President of the ANC mission-in-exile, to revive the cultural movement. In the mid-1970s, it was clear that many in the Black Consciousness Movement were at odds with Buthelezi’s politics. For instance, during the funeral of Robert Sobukwe he was barred from attending the service since they argued that he was a notable collaborator of the National Party government. In 1979, Inkosi Buthelezi and the Inkatha Yenkululeko Yesizwe, as it was then known, severed ties with the main ANC since the ANC favoured military strategies by employing the use of uMkhonto we Sizwe, “Spear of the Nation”. The meeting that was held in London between the two organisations did not succeed in ironing out differences.

In 1982, Buthelezi opposed the National Party government’s plan to cede the Ingwavuma region in northern Natal to the Government of Swaziland. The courts decided in his favour on the grounds that the government had not followed its own Black Constitution Act of 1972, which required consultation with the people of the region. He was also instrumental in setting up the teacher training and nursing colleges throughout the late-1970s and the early-1980s. He requested Harry Oppenheimer, his great friend and ally, to establish Mangosuthu Technikon in Umlazi, south of Durban. In 1993, he broke the record for the world’s longest-ever speech in an address he gave to the Natal legislature.

Buthelezi at first refused to stand at the 1994 general election, but chose to enter at the very last minute; after a meeting held on 8 April, where Mandela and De Klerk tried to sway the Zulu king, Goodwill Zwelithini kaBhekuzulu, from his dependence on Buthelezi by offering him a guarantee of special status of the Zulu monarchy after the election. The offer was not immediately successful, but Buthelezi seemed sympathetic to the idea. The foreign mediation team led by former US Secretary of State Henry Kissinger and former UK Foreign Secretary Peter Carrington were pivotal in reaching a compromise, and convinced the IFP leader to give up his boycott of the election. Buthelezi therefore signed an agreement with De Klerk and Mandela that guaranteed the ceremonial status of the Zulu king and was promised that foreign mediators would examine Inkatha’s claims to more autonomy in the Zulu area. It was probably too late though, because Buthelezi was losing support fast, and as a consequence, his party only narrowly won the elections in KwaZulu-Natal. In May 1994, Buthelezi was appointed Minister of Home Affairs in the first post-apartheid government, a position he retained following the 1999 general election. He was appointed as acting president a number of times during this period.

Following the 2004 election, Mbeki offered Buthelezi the Deputy Presidency, which he refused, as in exchange the IFP would have to relinquish the Premiership of the IFP-dominated province of KwaZulu-Natal. Since 1994, South Africa had been governed by a multi-party Government of National Unity, consisting of the ANC, the South African Communist Party, and the Congress of South African Trade Unions. By the time of the 1999 general election, a coalition agreement was not required, but the majority ANC again invited the IFP to join it in government. After the 2004 election, with Buthelezi declining the offer of the Deputy Presidency, the IFP left the coalition government and sat in the opposition benches.