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Summary Article: Dien Bien Phu, Battle of
from Encyclopedia of the Vietnam War: A Political, Social, and Military History

Start Date: March 13, 1954

End Date: May 7, 1954

Set-piece battle that ended the Indochina War. The siege of Dien Bien Phu was the most famous battle of the Indochina War and one of the great battles of the 20th century. In 1953 French military commander in Indochina General Henri Navarre decided to establish an airhead in northwestern Tonkin astride the main Viet Minh invasion route into Laos. Although not enthusiastic about the idea, Navarre believed that a strong base there would prevent an outright enemy invasion of Laos. The position would be located at the village of Dien Bien Phu, then held by a small Viet Minh garrison. Dien Bien Phu had a small airstrip and was some 185 miles by air from Hanoi.

In November 1953 Navarre in Saigon gave orders for the operation, dubbed castor, to proceed. On November 20, 2,200 French paras (paratroopers), the cream of the French Expeditionary Corps, dropped into the valley north and south of Dien Bien Phu. They easily defeated the few Viet Minh there and began establishing defensive positions.

With a hubris not unknown to other French military commanders in Indochina, Navarre completely underestimated his enemy. He expected to use superior French artillery and airpower to destroy any Viet Minh forces attacking Dien Bien Phu and assumed that at most Viet Minh commander General Vo Nguyen Giap would commit one division to such an effort. Should this belief prove incorrect, Navarre was confident that the garrison could be evacuated. Even in retrospect, it is hard to believe that he could have so seriously underestimated his enemy, given prior experience and especially the 1951-1952 Battle of Hoa Binh.

Hardly anyone had heard of Dien Bien Phu when the French occupied it. Dien Bien Phu was an obscure village situated in a valley surrounded by hills on all sides. To leave the enemy the opportunity to be in control of the high ground surrounding the base was dangerous, but as Navarre put it later, when the French arrived, the Viet Minh did not have artillery there.

Colonel Christian Marie Ferdinand de la Croix de Castries (promoted to brigadier general during the subsequent battle) commanded French forces at Dien Bien Phu. An aristocrat with a reputation of a playboy (the French strong points were reportedly named for his current mistresses), de Castries had wide experience in Indochina and was regarded as a capable commander. During the subsequent battle, however, he at times showed signs of detachment, seeming to withdraw mentally.

By the end of the first week, the French had 4,500 men in the valley. They were entirely dependent on air supply by a small number of transport aircraft (three groups totaling 75 Douglas C-47s Dakotas). The French also had available 48 Martin B-26 Marauder and Privateer bombers and 112 Bearcat and Hellcat fighter-bombers. There were also a few helicopters. After the battle Navarre wrote in his memoirs that “The insufficiency of aviation was, for our side, the principal cause of the loss of the battle.”

The Viet Minh on the other hand relied, as they had in previous battles, on the very primitive system of transport by human porters. Giap’s troops later improved Route 41 leading to Dien Bien Phu to enable the roadway to handle trucks and artillery pieces. At the end of April thanks to Chinese support, Giap had 14 transport companies with 800 trucks in a total of 1,200 to 1,300 vehicles. Nonetheless, the laborers (the “people’s porters,” Giap called them) remained the core of the Viet Minh supply system and were critical to the battle’s outcome.

The French central command post was in Dien Bien Phu itself. Around it de Castries ordered the construction of a series of strong points: Beatrice, Gabrielle, Anne-Marie, Dominique, Huguette, Françoise, Elaine, and Isabelle. Unfortunately for the French, Isabelle was separated from the others; some three miles to the south, it was easily cut off and diverted a third of the French forces.

De Castries had originally planned a wider defensive ring, perhaps 30 miles in length, but the problems of bringing everything in by air shrank the perimeter. Fortifications were also woefully inadequate. The French assumed that they could use airpower and counterbattery artillery fire to knock out any Viet Minh artillery before it became a problem. Indeed, the French were contemptuous of Viet Minh artillery capabilities. The French made no effort to camouflage their own positions and placed their own guns in open pits without protective cover. The Viet Minh easily observed French work from the hills, but French light observation aircraft failed to detect the Viet Minh buildup.

The Chinese directly supported the Viet Minh by handling some of the artillery batteries and helping to draw up fire plans. Chinese general Vy Quoc Thanh was also at Dien Bien Phu as military adviser and to help plan the campaign.

The French flew in reinforcements, but these were negated because Giap had not only called off his northern offensive but also decided to commit all available divisions to attack Dien Bien Phu. Thus, the defenders would encounter a much larger force than the single division that Navarre had anticipated. Giap also worked to cripple the French airlift capacity. In daring raids in early March, Viet Minh commandos attacked French air bases at Gia Lam near Hanoi and at Do Son and Cat Bi airfields near Haiphong, destroying 22 aircraft.

On November 20, 1953, 2,200 French “paras” dropped into the valley near Dien Bien Phu in northwestern Vietnam. They easily defeated the few Viet Minh there and established defensive positions. Both sides then built up their forces and, in the spring of 1954, the most important battle of the Indochina War occurred here. The Viet Minh defeat of the French paved the way for the French departure from Indochina. (AFP/Getty Images)

Meanwhile at Dien Bien Phu, the French had undertaken patrols. Ominously these were routinely mauled by the Viet Minh, and de Castries’s own chief of staff was killed just a few hundred yards from one of the strong points. The French then abandoned such patrolling as being counterproductive and providing little information about the enemy.

Giap now closed the ring on the French fortress. The 304th, 308th, 312th, and 316th divisions were brought to the area. The French called in airpower. Grumman F-8F Bearcats and Martin B-26 Marauder bombers attacked Viet Minh hill positions with bombs, napalm, and rocket fire, but the positions were well disguised by natural camouflage and were difficult to identify. The French also flew in 10 M-24 Chaffee light tanks by air and assembled them in the fortress under fire, although these had little impact on the battle.

By mid-February de Castries had sustained casualties of almost 1,000 men. The Viet Minh meanwhile continued to build their strength. Bernard Fall estimates that the Viet Minh ultimately assembled at Dien Bien Phu some 49,500 combat troops and 31,500 support personnel, mostly unskilled porters. An additional 23,000 troops maintained supply lines back to the Chinese border. In mid-March the French had 10,814 men in the valley, of whom about 7,000 were frontline combat troops. Fully a third of the garrison was Vietnamese, although most of these were tribal Thai. The Viet Minh thus enjoyed a superiority of approximately 5 to 1 in manpower, and they also had greater firepower.

The siege of Dien Bien Phu officially opened on March 13 with a heavy Viet Minh bombardment. Although the French added 4,000 men during the siege, Giap more than offset this with manpower increases of his own. He also steadily improved both the quantity and quality of his artillery. Ultimately the Viet Minh deployed 20 to 24 105-millimeter (mm) howitzers, 15 to 20 75-mm howitzers, 20 120-mm mortars, and at least 40 82-mm mortars. They also had some 80 Chinese-crewed 37-mm antiaircraft guns, 100 antiaircraft machine guns, and 12 to 16 six-tube Katyusha rocket launchers. During the battle, the Viet Minh fired 103,000 rounds of 75-mm or larger-size artillery shells, most of it by direct fire, simply aiming down their gun tubes at the French positions. Approximately 75 percent of French casualties came from artillery fire.

By contrast, French artillery assets were entirely inadequate. The French had only 4 155-mm howitzers, 24 105-mm howitzers, and 4 120-mm mortars. In contrast to the Viet Minh, the French fired only 93,000 shells during the battle and, unlike the Viet Minh, had difficulty identifying their targets.

On the very first night of the siege, March 13-14, the Viet Minh took Beatrice. Gabrielle fell two days later. Giap’s basic tactic was massive artillery fire followed by waves of infantry. The Viet Minh also brought the airstrip under fire to try to destroy F-8F Bearcat fighters there. One was destroyed on March 13, and two escaped to Vientiane. The next day three more got away to Cat Bi airfield; the remaining six were destroyed on the ground. The control tower was also badly damaged, and the radio beacon guiding planes there in bad weather was knocked out.

Pessimism now began to spread in the French command. In Hanoi, French commander in the north General René Cogny, who was never enthusiastic about the operation, now began to consider the possibility of losing the fortress. His resources were stretched thin, as Giap had sent the 320th Division, 3 autonomous regiments, and 14 regional battalions to disrupt the vital transportation link between Hanoi and Haiphong and divert French resources by attacking French outposts in the Tonkin Delta. The Viet Minh offensive there began on March 12, the day before the battle began at Dien Bien Phu. Thus, Cogny had to fight two battles at once. Navarre, who held to the primacy of central Indochina, refused all reinforcements to Cogny.

It is not surprising that de Castries’s pleas for reinforcements fell on deaf ears. Even ammunition was in short supply, as Viet Minh sappers blew up French stocks.

On March 22 the French used their last four tanks to counterattack People’s Army of Vietnam (PAVN, North Vietnamese Army) troops that had cut off Isabelle. This met up with units from Isabelle striking north. It was the first French success of the battle, but it cost 151 French dead, 72 wounded, and 1 missing. Viet Minh casualties were heavier, but Giap had a seemingly inexhaustible supply of manpower.

The arrival of the rainy season made conditions more miserable for attacker and defender alike and further complicated French resupply problems. C-47 transports still flew in supplies and evacuated wounded but at great risk. On March 26 one transport was shot down; two more were shot down on March 27. Late that same day one managed to land and pick up 19 wounded. This was the last flight in or out of Dien Bien Phu.

On March 26 Major Marcel Bigeard, who had parachuted into the fortress only 10 days before, commanded a successful attack against Viet Minh positions. Supported by artillery, fighter aircraft, and a tank platoon from Isabelle, the French paras sallied from the fortress to assault the Viet Minh. Bigeard later gave Viet Minh losses at 350 dead and more than 500 wounded as well as 10 taken prisoner. The raiders also captured 5 20-mm AA cannon, 12 .50-caliber machine guns, 2 bazookas, and 14 submachine guns and reclaimed 10 prisoners.

Battle of Dien Bien Phu, March 13-May 7, 1954

Having already suffered about 6,600 killed and 12,000 wounded, Giap’s force suffered from low morale, what Giap later called “right-wing tendencies.” Discussions led by political cadres about courage, right thinking, and dedication helped to restore morale, as did a more important change in tactics. Giap abandoned the costly human-wave attacks in favor of attrition warfare, resembling World War I. He pushed forward trenches until the particular target strong point was cut off from outside support.

The last stage of the battle was fought without letup in an area of about a square mile around the airstrip. The Viet Minh attacked on April 29, and by May 4 French senior officers knew there was no longer any hope. The last French reinforcements, 165 men of the 1st Colonial Parachute Battalion, jumped into the garrison during May 5-6. They had come at their own insistence to share the fate of their comrades. This brought the cumulative total of the garrison to 16,544 men. By now most of the airdrops of supplies were falling into Viet Minh hands. The final Viet Minh assault occurred on May 6, accompanied by the explosion of mines and the firing of Katyusha rockets. The last French troops surrendered on the evening of May 7.

During the siege, more than half of the French troops had been rendered hors de combat: 1,600 dead, 4,800 wounded, and 1,600 missing. The Viet Minh immediately sent their 8,000 prisoners off on foot on a 500-mile march to prison camps; less than half of them would return. Of the Vietnamese defenders taken, only 10 percent would be seen again. The Viet Minh had also shot down 48 French planes and destroyed 16 others on the ground. Viet Minh casualties are estimated at approximately 7,900 killed and 15,000 wounded.

The French had two plans to rescue the garrison. Operation CONDOR called for an infantry thrust from Laos to link up with airborne forces sent from Hanoi. Operation ALBATROSS was a plan for the garrison to break out on its own. Navarre did not order Cogny to begin planning for this until May 3. Not until May 7 did de Castries decide to attempt to execute the plan, but it was then too late. Another plan, code-named vulture, was also considered. This envisioned massive U.S. intervention in the form of air strikes, but President Dwight D. Eisenhower could not secure British support, and the plan was dropped.

The Battle of Dien Bien Phu was the death knell of the French in Asia. In Paris, Premier Joseph Laniel, dressed entirely in black, gave the news to the National Assembly. The Geneva Conference was already in progress to discuss a host of Asian issues, and the French defeat provided the politicians with an excuse to shift blame for the Indochina debacle to the military. Although France had not provided the troops or resources that the French military required to win the war, it could now blame the military for the defeat and extricate the nation from the Indochina morass. A new government under Pierre Mendès-France came to power to carry out that mandate. Almost immediately after the Indochina War, the French Army found itself transferred to Algeria to fight again. This time, the army promised, there would be no sellout.

See also

CASTOR, Operation; Cogny, René; De Castries, Christian Marie; Eisenhower, Dwight David; Geneva Conference and Geneva Accords of 1954; Laniel, Joseph; Mendès-France, Pierre; Navarre, Henri Eugène; Navarre Plan; VULTURE, Operation

  • Bigeard, General Marcel. Pour une parcelle de gloire. Paris: Plon, 1975.
  • Fall, Bernard B. Hell in a Very Small Place: The Siege of Dien Bien Phu. New York: Lippincott, 1966.
  • Morgan, Ted. Valley of Death: The Tragedy at Dien Bien Phu That Led America into the Vietnam War. New York: Random House, 2010.
  • Porch, Douglas. The French Foreign Legion: A Complete History of the Legendary Fighting Force. New York: HarperCollins, 1991.
  • 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.
  • Windrow, Martin. The Last Valley: Dien Bien Phu and the French Defeat in Vietnam. London: Weidenfeld and Nicolson, 2004.
  • Tucker, Spencer C.
    Copyright 2011 by ABC-CLIO, LLC

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