Harold Wilson was appointed Prime Minister of the United Kingdom by Queen Elizabeth II on 16 October 1964 and formed the first Wilson ministry, a Labour government, which held office with a thin majority between 1964 and 1966. In an attempt to gain a workable majority in the House of Commons, Wilson called a new election for 31 March 1966, after which he formed the second Wilson ministry, a government which held office for four years until 1970.

Margaret Hilda Thatcher, Baroness Thatcher, was a British stateswoman and Conservative politician who served as Prime Minister of the United Kingdom from 1979 to 1990 and Leader of the Conservative Party from 1975 to 1990. She was the longest-serving British prime minister of the 20th century and the first woman to hold the position. As prime minister, she implemented economic policies known as Thatcherism. A Soviet journalist dubbed her the "Iron Lady", a nickname that became associated with her uncompromising politics and leadership style.