On 9 March 1945, the Japanese defeated the Vichy French Decoux Government and took control of Vietnam, reinstating Bao Dai as a puppet emperor. The United States began friendly relations with the Viet Minh as early as 30 April 1945, after Major Archimedes Patti, of the US Office of Strategic Services, met with Ho Chi Minh and was received warmly.

On 14 August 1945, the Japanese surrendered to the Allies of World War II, ending that war. Though defeated, the Japanese (against the terms of their treaty) helped the Viet Minh take control of the government until the transitional occupation by the Nationalist Chinese forces in the north and the British occupation force in the south in early September 1945.

In late 1945, Ho Chi Minh and the Viet Minh began negotiations with the French; they distrusted the Chinese from both ideological and historical viewpoints. With the initial cooperation of the Viet Minh, the French returned in the beginning of the following year and rapidly reestablished their authority. Once he decided his goal was met, Ho Chi Minh let relations between the Viet Minh and the French gradually fall apart.

Battle of Dien Bien Phu