Julius Kambarage Nyerere was a Tanzanian anti-colonial activist, politician and political theorist. He governed Tanganyika as prime minister from 1961 to 1962 and then as president from 1962 to 1964, after which he led its successor state, Tanzania, as president from 1964 to 1985. He was a founding member and chair of the Tanganyika African National Union (TANU) party, and of its successor Chama Cha Mapinduzi, from 1954 to 1990. Ideologically an African nationalist and African socialist, he promoted a political philosophy known as Ujamaa.

Tanganyika was a sovereign state, comprising the mainland part of present-day Tanzania, that existed from 1961 until 1964. It first gained independence from the United Kingdom on 9 December 1961 as a Commonwealth realm headed by Queen Elizabeth II before becoming a republic within the Commonwealth of Nations a year later. After signing the Articles of Union on 22 April 1964 and passing an Act of Union on 25 April, Tanganyika officially joined with the People's Republic of Zanzibar to form the United Republic of Tanganyika and Zanzibar on Union Day, 26 April 1964. The new state changed its name to the United Republic of Tanzania within a year.