The Vietnam War was fought to determine which political regime would gain control of the country and reunify it after French occupation. France backed Emperor Bao Dai in South Vietnam, while the majority of Vietnamese citizens supported Ho Chi Minh in the northern Democratic Republic of Vietnam. After the French defeat of 1954, the resultant treaty proposed a 1956 nationwide election to unify Vietnam. Instead, President Ngo Dinh Diem enlisted U.S. support to oppose Ho Chi Minh’s Communist agenda.
The Vietnam War stemmed from a decades-long conflict that started with 19th-century French imperialism. Vietnam was under French administrative control when Japan invaded during World War II, spurring revolutionary forces under Ho Chi Minh’s leadership to launch a resistance movement against both opponents. Emperor Bao Dai gained control after Japan withdrew, causing the League for the Independence of Vietnam, or Viet Minh, to mobilize against the French-educated leader. Ho Chi Minh idealized the Communist principles of China and the Soviet Union, and he seized Hanoi as the center of his new regime.
With French support, Bao established Saigon as the capital of South Vietnam. However, France was never able to regain the northern territories of Vietnam, and Bao was eventually deposed by Ngo Dinh Diem. Despite the Viet Minh’s revolutionary goals, Ngo Dinh Diem’s corrupt rule and lack of popular support, the United States offered military and financial resources to South Vietnam to prevent the rise of another strong Communist regime.