The Battle of Điện Biên Phủ was a defeat of the French Union forces by the Viet Minh forces in the First Indochina War. It took place between 13 March and 7 May 1954.
The French began an operation to insert, and support, their soldiers at Điện Biên Phủ, deep in the autonomous Tai Federation in northwest Tonkin. The operation's purpose was to cut off enemy supply lines into the neighboring Kingdom of Laos (a French protectorate) and draw the Viet Minh into a major confrontation in order to cripple them. The French based their forces in an isolated but well-fortified camp that would be resupplied by air, a strategy adopted based on the belief that the Viet Minh had no anti-aircraft capability.
The communist 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 up the rear slopes of the mountains. They dug tunnels 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 protective cover.
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 aircraft were shot down and runways were destroyed.
After a two-month siege, the garrison was overrun, with the surviving French forces forced to surrender. Although it did not significantly alter the strategic situation in Indochina, the defeat at Điện Biên Phủ brought a profound psychological shock to France. It led to a gradual withdrawal of French forces from all of Indochina (with the exception of Laos). This was agreed in the 1954 Geneva Accords signed ten weeks after the battle. Accordingly, Vietnam was also temporarily divided at the 17th parallel, with the North assigned to the Democratic Republic of Vietnam under Ho Chi Minh, and the South to the State of Vietnam under Bao Dai and Ngo Dinh Diem.
Background
Military situation
By 1953, the First Indochina War created multiple complications for the French army. A succession of commanders – Philippe Leclerc de Hauteclocque, Jean Étienne Valluy, Roger Blaizot, Marcel Carpentier, Jean de Lattre de Tassigny, and Raoul Salan – had proven incapable of suppressing the insurrection of the Viet Minh, who were fighting for independence. During their 1952–1953 campaign, the Viet Minh had overrun vast swathes of Laos, Vietnam's western neighbor, advancing as far as Luang Prabang and the Plain of Jars. The French were unable to slow the advance of the Viet Minh, who fell back only after outrunning their always-tenuous supply lines. In 1953, the French had begun to strengthen their defenses in the Hanoi delta region to prepare for a series of offensives against Viet Minh staging areas in northwest Vietnam. They set up fortified towns and outposts in the area, including Lai Châu near the Chinese border to the north, Nà Sản to the west of Hanoi, and the Plain of Jars in northern Laos.
In May 1953, French Premier René Mayer named Henri Navarre as Salan's successor to command French Union forces in Indochina. Mayer had given Navarre a single order—to create military conditions that would lead to an "honorable political solution". According to military scholar Phillip Davidson:
On arrival, Navarre was shocked by what he found. There had been no long-range plan since de Lattre's departure. Everything was conducted on a day-to-day, reactive basis. Combat operations were undertaken only in response to enemy moves or threats. There was no comprehensive plan to develop the organization and build up the equipment of the Expeditionary force. Finally, Navarre, the intellectual, the cold and professional soldier, was shocked by the "school's out" attitude of Salan and his senior commanders and staff officers. They were going home, not as victors or heroes, but then, not as clear losers either. To them the important thing was that they were getting out of Indochina with their reputations frayed, but intact. They spared little thought or concern for the problems of their successors.
Nà Sản and the hedgehog concept
Navarre began searching for a way to address the Viet Minh threat to Laos. Colonel Louis Berteil, commander of Mobile Group 7 and Navarre's main strategist, formulated the hérisson ('hedgehog') concept. The French army would establish a fortified airhead by airlifting soldiers to positions adjacent to key Viet Minh supply lines to Laos. They would cut off Viet Minh soldiers fighting in Laos and force them to withdraw. "It was an attempt to interdict the enemy's rear area, to stop the flow of supplies and reinforcements, to establish a redoubt in the enemy's rear and disrupt his lines".
The hérisson was based on French experiences at the Battle of Nà Sản. In late November and early December 1952, Giáp had attacked the French outpost at Nà Sản, which was essentially an "air-land base", a fortified camp supplied only by air. There, the French beat back Giáp's forces repeatedly, inflicting very heavy losses on them. The French hoped that by repeating the strategy on a much larger scale, they would be able to lure Giáp into committing the bulk of his forces to a massed assault. This would enable superior French artillery, armor, and air support to decimate the exposed Viet Minh forces. The success at Nà Sản convinced Navarre of the viability of the fortified airhead concept.
However, French staff officers failed to treat seriously several crucial differences between Điện Biên Phủ and Nà Sản: First, at Nà Sản, the French commanded most of the high ground with overwhelming artillery support. At Điện Biên Phủ, however, the Viet Minh controlled much of the high ground around the valley, their artillery far exceeded French expectations, and they outnumbered the French troops four to one. Giáp compared Điện Biên Phủ to a "rice bowl", where his troops occupied the edge and the French the bottom. Second, Giáp made a mistake at Nà Sản by committing his forces to reckless frontal attacks before being fully prepared. He learned his lesson: at Điện Biên Phủ, Giáp spent months meticulously stockpiling ammunition and emplacing heavy artillery and anti-aircraft guns before making his move. He obtained crucial intelligence on French artillery positions from Viet Minh spies posing as camp laborers. Artillery pieces were sited within well-constructed and camouflaged casemates. As a result, when the battle finally began, the Viet Minh knew exactly where the French artillery pieces were, while the French did not even know how many guns Giáp possessed. Third, the aerial resupply lines at Nà Sản were never severed, despite Viet Minh anti-aircraft fire. At Điện Biên Phủ, Giáp made it a priority for his gunners to focus on the French runways and aircraft, crippling supply runs and making it impossible for fresh soldiers to be sent in.
Prelude
Lead up to Castor
In June 1953, Major General René Cogny, the French commander in the Tonkin Delta, proposed Điện Biên Phủ, which had an old airstrip built by the Japanese during World War II, as a "mooring point". In another misunderstanding, Cogny envisioned a lightly defended point from which to launch raids; Navarre, however, believed that he intended to build a heavily fortified base capable of withstanding a siege. Navarre selected Điện Biên Phủ for Berteil's "hedgehog" operation. When presented with the plan, every major subordinate officer – Colonel Jean-Louis Nicot (commander of the French Air transport fleet), Cogny, and Generals Jean Gilles and Jean Dechaux (the ground and air commanders for Operation Castor, the initial airborne assault on Điện Biên Phủ) – protested. Cogny pointed out, presciently, that "we are running the risk of a new Nà Sản under worse conditions". Navarre rejected the criticisms of his proposal and concluded a 17 November conference by declaring that the operation would begin three days later, on 20 November 1953.
Navarre decided to go ahead with the plan despite serious operational difficulties. These later became painfully obvious, but at the time may have been less apparent. He had been repeatedly assured by his intelligence officers that the operation carried very little risk of involvement by a strong enemy force. Navarre had previously considered three other approaches to defending Laos: mobile warfare, which was impossible given the terrain in Vietnam; a static defense line stretching to Laos, which was not feasible given the number of troops at Navarre's disposal; or placing troops in the Laotian provincial capitals and supplying them by air, which was unworkable due to the distance from Hanoi to Luang Prabang and Vientiane. Navarre believed that this left only the hedgehog option, which he characterized as "a mediocre solution". The French National Defense Committee ultimately agreed that Navarre's responsibility did not include defending Laos. However, its decision, which was drawn up on 13 November, was not delivered to him until 4 December, two weeks after the Điện Biên Phủ operation began.
Establishment of air operations
Operations at Điện Biên Phủ began at 10:35 on 20 November 1953. In Operation Castor, the French dropped or flew 9,000 troops into the area over three days, as well as a bulldozer to prepare the airstrip. They were landed at three drop zones: "Natasha" (northwest of Điện Biên Phủ), "Octavie" (to the southwest), and "Simone" (to the southeast). The Viet Minh elite 148th Independent Infantry Regiment, headquartered at Điện Biên Phủ, reacted "instantly and effectively". Three of its four battalions, however, were absent. Initial operations proceeded well for the French. By the end of November, six parachute battalions had been landed, and the French Army consolidated its positions.
It was at this time that Giáp began his countermoves. He had expected an attack but had not foreseen when or where it would occur. Giáp realized that, if pressed, the French would abandon Lai Châu Province and fight a pitched battle at Điện Biên Phủ. On 24 November, Giáp ordered the 148th Infantry Regiment and the 316th Division to attack Lai Chau, while the 308th, 312th, and 351st divisions assaulted Điện Biên Phủ from Việt Bắc.
Starting in December, the French, under the command of Colonel Christian de Castries, began transforming their anchoring point into a fortress by setting up seven satellite positions. (Each was said to be named after a former mistress of de Castries, although the allegation is probably unfounded, as the eight names begin with letters from the first nine of the alphabet.) The fortified headquarters was centrally located, with positions Huguette to the west, Claudine to the south, and Dominique to the northeast. The other positions were Anne-Marie to the northwest, Beatrice to the northeast, Gabrielle to the north, and Isabelle 6 km (3.7 mi) to the south, covering the reserve airstrip.
The arrival of the 316th Viet Minh Division prompted Cogny to order the evacuation of the Lai Chau garrison to Điện Biên Phủ, exactly as Giáp had anticipated. En route, they were virtually annihilated by the Viet Minh. "Of the 2,100 men who left Lai Chau on 9 December, only 185 made it to Điện Biên Phủ on 22 December. The rest had been killed, captured, or "deserted".
French military forces had committed 10,800 troops, together with yet more reinforcements, totalling nearly 16,000 men, to the defense of a monsoon-affected valley surrounded by heavily-wooded hills and high ground that had not been secured. Artillery as well as ten US M24 Chaffee light tanks (each broken down into 180 individual parts, flown into the base, and then re-assembled) and numerous aircraft (attack and supply types) were committed to the garrison. A number of quadruple 0.50 calibre machine guns were present and used in the ground role. This included France's regular troops (notably elite paratrooper units, plus those of the artillery), French Foreign Legionnaires, Algerian and Moroccan tirailleurs (colonial troops from North Africa) and locally-recruited Indochinese (Laotian, Vietnamese and Cambodian) infantry.
In comparison, altogether the Viet Minh had moved up to 50,000 regular troops into the hills surrounding the French-held valley, totalling five divisions, including the 351st Heavy Division, which was an artillery formation equipped with medium artillery, such as the US M101 105mm howitzer, supplied by the neighbouring People's Republic of China (PRC) from captured stocks obtained from defeated Nationalist China as well as US forces in Korea, together with some heavier field-guns as well as anti-aircraft artillery. Various types of artillery and anti-aircraft guns (mainly of Soviet origin), which outnumbered their French counterparts by about four to one, were moved into strategic positions overlooking the valley and the French forces based there. The French garrison came under sporadic direct artillery fire from the Viet Minh for the first time on 31 January 1954 and patrols encountered the Viet Minh troops in all directions around them. The French were completely surrounded.
Giáp's change of strategy
Originally, the planned Viet Minh attack was based on the Chinese "Fast Strike, Fast Victory" model, which aimed to use all available power to thrust into the command center of the base to secure victory, but this was changed to the "Steady Fight, Steady Advance" model of siege tactics.
The battle plan designed on the fast strike model was due to open at 17:00 on 25 January and to finish three nights and two days later. Nevertheless, this start date was delayed to 26 January, because on 21 January Viet Minh's intelligence indicated that the French had grasped this plan.