The Battle of Dien Bien Phu was the climactic confrontation of the First Indochina War between the French Union's French Far East Expeditionary Corps and Viet Minh communist-nationalist revolutionaries. It was, from the French view before the event, a set piece battle to draw out the Vietnamese and destroy them with superior firepower. The battle occurred between March and May 1954 and culminated in a comprehensive French defeat that influenced negotiations underway at Geneva among several nations over the future of Indochina.

After the battle France agreed to withdraw its forces from all its colonies in French Indochina, while stipulating that Vietnam would be temporarily divided at the 17th parallel, with control of the north given to the Viet Minh as the Democratic Republic of Vietnam under Ho Chi Minh, and the south becoming the State of Vietnam, nominally under Emperor Bảo Đại, preventing Ho Chi Minh from gaining control of the entire country. The refusal of Ngô Đình Diệm (the US-supported president of the first Republic of Vietnam) to allow elections in 1956, as had been stipulated by the Geneva Conference, eventually led to the Vietnam War.

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