East African Federation (1960-1964)
In 1960, prior to the declaration of independence in Kenya, Tanganyika, Uganda and Zanzibar, a union between the four British territories was proposed.
Tanganyika wanted to delay its imminent independence in 1960 so that the four territories could achieve independence together as one federation.
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All the leaders agreed in 1963 to work towards a federation, but by 1964, the plan collapsed after disputes over leadership the federation among others. Tanganyika and Zanzibar eventually united in 1964 to form Tanzania.