The responsibility for, and the exact events, details, and decisions made in the days leading up to the outbreak of full-scale war between the French 4th Republic and the Democratic Republic of Vietnam (DRV) on the evening of 19 December 1946 remain unclear and contested on many counts to this day. At the heart of the problem was a clash over two opposing conceptions of who should and would control Vietnam in the wake of the Japanese overthrow of French Indochina in March 1945 and the subsequent Japanese defeat five months later. On the one hand, the French were determined to rebuild a new colonial Indochina of a pentagonal, federal nature, consisting of Cambodia, Laos, Cochinchina, Annam and Tonkin. On the other hand, Vietnamese nationalists were equally determined to create a unified and eventually independent Vietnamese nation-state. While some in Ho Chi Minh’s entourage may have wanted to take up arms early on to make this happen, the DRV’s president did not seek a violent clash with the French. In spite of the outbreak of a limited war below the 16th parallel on 23 September 1945, Ho Chi Minh appealed to the Chinese, the United States, the Soviet Union, the British, newly independent Asian states, and the United Nations to support the Vietnamese case for a negotiated settlement.
For a short time, in mid-1946, just such a deal seemed possible. Under Chinese pressure, Ho Chi Minh and Jean Sainteny (representing France) signed the Accords of 6 March 1946, agreeing to refer to Vietnam as “a free state” within the French Indochinese Federation and French Union on the condition that a referendum were held on the unification of Cochinchina with the rest of Vietnam. A military annex to the accord authorized the French to station 15,000 troops in northern Vietnam to replace the withdrawing Chinese troops. However, the French high commissioner for Indochina, Admiral Georges Thierry d’Argenlieu, was hostile to the idea of a unitary Vietnam and determined to roll back the DRV’s sovereignty in order to create the Indochinese Federation, as instructed by General Charles de Gaulle. On 1 June 1946, as Ho was leaving to continue negotiations in France, Thierry d’Argenlieu formally announced the existence of the Provisional Government of the Republic of Cochinchina as one of his steps towards the creation of the Indochinese Federation. Despite the French failure to move on the March Accords during the Fontainebleau Conference in mid-1946, Ho Chi Minh settled for a modus vivendi in September, including a cease-fire in southern Vietnam, hoping that this would provide him with much needed time and that a shift to the left in French metropolitan politics would make it possible to achieve an agreement.
Things took a turn for the worse in late 1946, however. Having retaken all of Laos above the 16th parallel in mid-1946 and all Chinese troops now evacuated from northern Indochina by September, French authorities in Indochina intensified their brinksmanship with the DRV. As a result, Franco-Vietnamese relations worsened dramatically in November 1946 when local French officers presented ultimatums to DRV forces during the Haiphong and Langson incidents. Not only did Thierry d’Argenlieu support these actions, but his superiors in Paris also covered him and in so doing only emboldened the admiral. Tensions rose further in December as skirmishes broke out, confidence plummeted, and preparations for war began on both sides. While the Vietnamese began evacuating the population, vital ministries, equipment, and personnel from Hanoi, Ho Chi Minh tried nonetheless to head off full-scale war, hoping to the last minute that the constitution of a sympathetic government in Paris under the socialist President Léon Blum would provide him with a serious interlocutor with whom he could negotiate a way out of what had become a blind alley. However, time was too short, communications were bad, and mutual confidence was at an all time low. Many French authorities in Indochina and Vietnamese in Ho’s own entourage wanted a showdown.
On the evening of 19 December 1946, in a still contested and very unclear sequence of events, war broke out in Hanoi, marking what historians consider to be the full-scale outbreak of the Indochina War. At the time, the DRV accused the French of starting the war, while the French claimed the opposite. While it seems well established that it was the Vietnamese who opened the hostilities on 19 December, the jury is still out as to the circumstances in which the attack occurred. To date, French historians Philippe Devillers and Frédéric Turpin and Norwegian scholar Stein Tønnesson have provided the hardest, archival evidence showing the degree to which French political and military authorities in Indochina had been preparing since at least April 1946 for the reoccupation of northern Indochina, even if it meant war with the DRV. Such action was in line with de Gaulle’s instructions of mid-1945. However, it remains unclear whether the DRV fell into a deliberately set French trap on 19 December, designed to head off negotiations with Léon Blum; whether it was the inability of Ho Chi Minh to control his subordinates in such explosive circumstances; or whether it was the result of a deliberate Vietnamese order to attack. Until more evidence comes to light, one can only conclude that with their backs up against the wall since November, the Vietnamese finally lashed out when militia forces cut the electricity in Hanoi at 20H00.
French commanders in the north were only too happy to respond with force. While Vo Nguyen Giap never committed the bulk of his forces to defending the capital, the DRV instructed militia forces and the Capital Brigade to pin down the French in the city in order to allow the government to make it to safe zones. Two months of fierce street fighting ensued, in what the Vietnamese refer to as the battle of Hanoi. The French army would not fully reoccupy the capital until late February 1947. The fledgling French 4th Republic was now engaged in a colonial war and the newly born DRV had begun what would turn out to be a 30 year war of national liberation. See also COUP DE FORCE OF 9 MARCH 1945; FRANCO-CHINESE ACCORD (28 FEBRUARY 1946).