Vietnam had been under French colonial control since the 19th century, and during World War II, it was invaded by Japanese occupiers. In order to fight off Japanese and French occupiers, in 1941, the political leader Ho Chi Minh, who dedicated communist, formed the League for the Independence of Vietnam, which was also called Viet Minh.

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After its defeat in the WWII in 1945, Japan withdrew its forces from Vietnam, leaving the Emperor Bao Dai in control. Seeing an opportunity to seize control, Ho’s Viet Minh forces rose up, taking over the northern city of Hanoi and declaring a Democratic Republic of Vietnam there, with Ho as the president. Attempting to regain control of the region, Emperor Bao, backed by France, set up the state of Vietnam in July 1949 with Saigon as the capital city.


By 1954, Vietnam was divided into two parts: the North having a Marxist-Leninist system led by the communist Ho, and south having a noncommunist government led by Bao. Both sides wanted a unified Vietnam, but Ho and his supporters wanted it modeled after other communist countries, while Bao and many others wanted a Vietnam with close ties to the West.

In 1954, Bao Dai appointed Ngo Dinh Diem, a South Vietnamese politician, the prime minister of the State of Vietnam. In 1955, with the support of the U.S., Diem deposed Bao and established the first Republic of Vietnam, declaring himself the president.

Source: http://www.history.com/topics/vietnam-war/vietnam-war-history