On August 26, 1914, the German protectorate of Togoland was invaded by French and British forces and fell after five days of brief resistance. Togoland was divided into French and British administrative zones in 1916, and following the war, Togoland formally became a League of Nations mandate divided for administrative purposes between France and the United Kingdom.
After World War II, the mandate became a UN trust territory, still administered by French commissioners.
By statute in 1955, French Togoland became an autonomous republic within the French union, although it retained its UN trusteeship status. A legislative assembly elected by universal adult suffrage had considerable power over internal affairs, with an elected executive body headed by a prime minister responsible to the legislature. These changes were embodied in a constitution approved in a 1956 referendum. On September 10, 1956, Nicolas Grunitzky became prime minister of the Autonomous Republic of Togo. However, due to irregularities in the plebiscite, an unsupervised general election was held in 1958 and won by Sylvanus Olympio. On April 27, 1960, in a smooth transition, Togo severed its constitutional ties with France, shed its UN trusteeship status, and became fully independent under a provisional constitution with Olympio as president.