1954: French defeated at Dien Bien Phu

On this day, Dien Bien Phu, a major French stronghold in northwest Vietnam, falls to the Vietnamese Communists after 57 days of siege. In 1949, Ho Chi Minh's Viet Minh launched a guerrilla war against the French, who were struggling to retain their colonial interest in the country. In 1953, the French, weary of jungle warfare, occupied Dien Bien Phu, hoping to draw the Viet Minh out into the open. The Viet Minh attacked the fortified French position, and by March of 1954, roughly 50,000 communist troops had encircled Dien Bien Phu. On May 7, the French positions collapsed. Although the defeat brought an end to French colonial efforts in Indochina, the United States soon stepped up to fill the vacuum, increasing military aid to South Vietnam and sending the first U.S. military advisers to the country in 1959.