In early 1954 Viet Minh commander General Vo Nguyen Giap planned to invade Laos with five divisions. He hoped to take all of Laos and perhaps Cambodia and then link up with Viet Minh forces operating in southern Vietnam. In response, French commander in Indochina General Henri Navarre implemented Operation castor, the establishment of a base in the village of Dien Bien Phu in far northwestern Vietnam. Navarre hoped to use this as a blocking position astride the chief Viet Minh invasion route into northern Laos but also as bait to draw into battle Viet Minh forces and destroy them with superior French artillery and airpower.
Located in a remote valley some 200 miles by air from Hanoi, Dien Bien Phu had a small airstrip. On 20 November 1953, 2,200 French paratroopers dropped into the valley and easily swept aside a small Viet Minh contingent. Navarre assumed that at most Giap would commit one division to Dien Bien Phu. The French were confident that in any case, the garrison could easily be evacuated. Navarre did not worry about controlling the hills around Dien Bien Phu because, as he pointed out, the Viet Minh did not have any artillery there. This turned out to be a serious misapprehension.
Colonel Christian de Castries commanded the French forces at Dien Bien Phu. The men there were entirely dependent on air supply by some 75 C-47 Dakotas. For ground support, the French could call on 48 B-26 and Privateer bombers, 112 Bearcat and Hellcat fighter-bombers, and several helicopters. Castries established his central command post in the village and ordered construction around it of a series of strong points, reportedly all named for his mistresses: Beatrice, Gabrielle, Anne-Marie, Dominique, Huguette, Françoise, Elaine, and Isabelle. The location of Isabelle was unfortunate; it was 3 miles to the south, separated from the others. Easily cut off, it also tied down a third of the French forces. The French fortifications were also inadequate (all equipment had to be brought in by air), but Castries assumed that his artillery could quickly knock out any enemy guns that could be brought against him. By mid-March the French had nearly 11,000 men in the valley, a third of them ethnic Vietnamese. Ultimately the French committed 16,544 men there.
Giap accepted the challenge, but there was political pressure on him to do so. A diplomatic conference among the great powers to discuss Asia was about to begin in Geneva, and Viet Minh leader Ho Chi Minh believed that a major military victory might force the French into negotiations to end the war. Giap committed four divisions of some 49,500 combat troops, along with 31,500 support personnel.
The siege opened on 13 March 1954 with a heavy Viet Minh bombardment. Although the French added 4,000 men during the battle, Giap more than offset this with increases of his own and steadily strengthened his artillery, with thousands of porters dragging the guns by hand there. Ultimately the Viet Minh deployed more artillery pieces at Dien Bien Phu and fired more rounds than did the French. The French possessed only four 155mm howitzers, twenty-four 105mm howitzers, and four 120mm mortars. The Viet Minh deployed twenty to twenty-four 105mm howitzers, fifteen to twenty 75mm howitzers, twenty 120mm mortars, and at least forty 82mm mortars along with eighty Chinese-crewed 37mm antiaircraft guns, one hundred antiaircraft machine guns, and twelve to sixteen 6-tube Katyusha rocket launchers.
On the very first night of the siege, 13–14 March, the Viet Minh took Beatrice. Gabrielle fell two days later. The Viet Minh also shelled the airstrip, destroying or driving away French aircraft and knocking out the radio direction beacon, which was critical for aerial resupply. C-47s still flew in supplies and evacuated wounded, but at great risk. The last flight in or out of the fortress occurred on 27 March. During the battle, the Viet Minh shot down forty-eight French planes and destroyed another sixteen on the ground.
On 22 March the French used the last four of their ten U.S.-supplied M24 Chaffee light tanks to counterattack Viet Minh troops that had cut off Isabelle. The first French success of the battle, it also claimed 151 French dead. The arrival of the rainy season made conditions miserable for defender and attacker alike. Heavy casualties from costly Viet Minh human-wave tactics created morale problems and forced Giap to call a halt and then shift to classic siege warfare of trenches inching ever closer to the French lines. The final assault occurred on 6 May, and the last French troops surrendered on the evening of 7 May.
In the battle the French sustained some 20,000 casualties: 2,242 killed, 3,711 missing, 6,463 wounded, and 6,500 prisoners, not counting those forces lost in relief operations. The Viet Minh took some 22,900 casualties: 7,900 killed and 15,000 wounded. A plan to rescue the garrison or to break out came too late. Meanwhile, the Viet Minh immediately sent their 6,500 prisoners off on foot on a 500-mile trek to prison camps from which fewer than half would return.
Although the battle had tied down Viet Minh resources, it had not helped the French situation elsewhere in Indochina. The outcome of the battle also allowed French political leaders to shift the blame for the defeat in Indochina to the French Army. Pierre Mendès-France became premier and announced his intention to secure a peace settlement at Geneva. Although the peace agreement was reached that July, it proved to be only a truce.
Spencer C. Tucker
Bamberg, James. British Petroleum and Global Oil, 1950-75: The Challenge to Nationalism. Cambridge: Cambridge University Press, 2000.; Navarre, Henri. Agonie de l'Indochine, 1953–1954. Paris: Librairie Plon, 1956.; Roy, Jules. The Battle of Dienbienphu. New York: Harper and Row, 1965.; Simpson, Howard R. Dien Bien Phu: The Epic Battle America Forgot. Washington, DC: Brassey's, 1994.