Battle of Dien Bien Phu

The Battle of Điện Biên Phủ was a climactic confrontation of the First Indochina War that took place between 13 March and 7 May 1954. It was fought between the French Union's colonial Far East Expeditionary Corps and Viet Minh communist revolutionaries. The United States was officially not a party to the war, but it was secretly involved by providing financial and material aid to the French Union, which included CIA contracted American personnel participating in the battle. The People's Republic of China and the Soviet Union similarly provided vital support to the Viet Minh, including most of their artillery and ammunition.

The French began an operation to insert, and support, their soldiers at Điện Biên Phủ, deep in the autonomous Tai Federation up in the hills northwest of Tonkin. The operation's purpose was to cut off Viet Minh supply lines into the neighboring Kingdom of Laos (a French ally), and draw the Viet Minh into a major confrontation in order to cripple them. The plan was to resupply the French position by air, a strategy adopted based on the belief that the Viet Minh had no anti-aircraft capability. The French forces were a diverse mix of Foreign Legionnaires, former SS of the Russian Front (to whom, in 1945, the French had given the choice between Indochina and the firing squad), and all kinds of nationals from Dutch to Thai and Tahitians, out of which the French formed a minority.

The Viet Minh, however, under General Võ Nguyên Giáp, surrounded and besieged the French. They brought in vast amounts of heavy artillery (including anti-aircraft guns) and managed to move these bulky weapons through difficult terrain by individual men and women up the rear slopes of the mountains. They dug tunnels through the mountains and arranged the guns to target the French positions. The tunnels featured a front terrace, onto which the Viet Minh would pull their cannons from out of the tunnels, fire a few shots, to then pull them back into the protective cover of the tunnels. In 54 days of gun battle, no Viet Minh cannon was destroyed.

In March, the Viet Minh began a massive artillery bombardment of the French defenses. The strategic positioning of their artillery made it nearly impervious to French counter-battery fire. Tenacious fighting on the ground ensued, reminiscent of the trench warfare of World War I. At times, the French repulsed Viet Minh assaults on their positions while supplies and reinforcements were delivered by air. As key positions were overrun, the perimeter contracted, and the air resupply on which the French had placed their hopes became impossible. As the Viet Minh anti-aircraft fire took its toll and artillery bombarded the airstrip, effectively preventing takeoffs and landings, fewer and fewer of those supplies reached the French.

The garrison was overrun in May after a two-month siege, and most of the French forces surrendered. A few men escaped to Laos. Among the 11,721 French troops captured, 858 of the most seriously wounded were evacuated via the Red Cross mediation in May 1954, only 3,290 were returned four months later. The French government in Paris resigned. The new Prime Minister, the left-of-centre Pierre Mendès France, supported French withdrawal from Indochina.

The Battle of Điện Biên Phủ was decisive. The war ended shortly afterward and the 1954 Geneva Accords were signed. 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. With huge support by the U.S., the south becoming the State of Vietnam, nominally under Emperor Bảo Đại, preventing Ho Chi Minh from gaining control of the entire country.