After WWII, the decolonization of French Indochina left the region divided into four independent states: North Vietnam, South Vietnam, Cambodia, and Laos.

In September 1945, a provisional government in Hanoi declared the independence of the Democratic Republic of Viet Nam (DRV). The war that followed between the communist-led forces of the DRV and the forces of the French Union led to the creation of the two Vietnamese states, each claiming to embody the true national identity.
Source: Joint Chiefs of Staff

Việt Minh (abbreviated from Việt Nam độc lập đồng Minh) — English: League for the Independence of Vietnam, was a coalition formed by Hồ Chí Minh in May1941.
In early 1950 the Viet Minh had shifted from guerilla to conventional warfare, and for the next four years, large-scale assaults ranging upward to 14-battalion strikes — were not uncommon.
In 1952 a three-division assault in one province forced the withdrawal of over 20,000 French troops.
In 1952-53 nearly 6,000 French and Legionnaires troops were killed, as well as 7,730 of their Vietnamese allies.

“The United States decision to provide military assistance to France and the Associated States of Indochina was announced in May 1950…. The decision was taken in spite of the U.S. desire to avoid direct involvement in a colonial war, and in spite of a sensing that France’s political-military situation in Indochina was bad and was deteriorating. Moreover, predictions that U.S. aid would achieve a marked difference in the course of the Indochina War were heavily qualified.“