The First Indochina War (also known as the French Indochina War, the The Anti-French War, the Franco-Vietnamese War, the Franco-Vietminh War, the Indochina War and the Dirty War in France and in contemporary Vietnam, as the French War) is fought in French Indochina from December 19, 1946 until August 1, 1954 between the French Union's French Far East Expeditionary Corps, led by France and supported by Bao Dai’s Vietnamese National Army against the Viet Mink, led by Ho Chi Minh and Vo Nguyen Giap.

Most of the fighting takes place in Tonkin in Northern Vietnam, although the conflict engulfs the entire country and also extends into the neighboring French Indochina protectorates of Laos and Cambodia.Following the reoccupation of Indochina by the French following the end of the Second World War, the area having fallen to the Japanese, the Viet Minh launch a rebellion against the French authority governing the colonies of French Indochina.

The first few years of the war involve a low-level rural insurgency against French authority.

However, after the Chinese communists reach the Northern border of Vietnam in 1949, the conflict becomes a conventional war between two armies equipped with modern weapons supplied by the United States and the Soviet Union.

French Union forces include colonial troops from the entire former empire (Moroccan, Algerian, Tunisian, African, Laotian, Cambodian, Vietnamese and Vietnamese ethnic minorities) and professional troops (European of the French Foreign Legion).

The use of metropolitan recruits is forbidden by the governments to prevent the war from becoming even more unpopular at home.

It is called the "dirty war" (la sale guerre) by the French communists and leftist intellectuals (including Sartre) during the Henri Martin affair in 1950.While the strategy of pushing the Viet Minh to attack a well-defended base in a remote part of the country at the end of their logistical trail is validated at the Battle of Na San, the lack of building materials (especially concrete), tanks (because of lack of road access and difficulty in the jungle terrain), and air cover precludes an effective defense.

The French are defeated with significant losses among their most mobile troops, particularly through ambush.After the war, the Geneva Conference on July 21, 1954, makes a provisional division of Vietnam at the 17th parallel, with control of the north given to the Viet Minh as the Democratic Republic of Vietnam under Ho Chi Minh, and the south becoming the State of Vietnam under Emperor Bao Dai.

A year later, Bao Dai will be deposed by his minister, Ngo Dinh Diem, creating the Republic of Vietnam.

Diem's refusal to enter into negotiations with North Vietnam about holding nationwide elections in 1956, as had been stipulated by the Geneva Conference, will eventually lead to war breaking out again in South Vietnam in 1959 - the Second Indochina War.