The Vietnam War was the deadliest conflict of the Cold War and fought between communist North Vietnam and the government of South Vietnam from November 1, 1955-April 30, 1975 with North Vietnam becoming the victors. The North, was supported by communist countries such as the People's Republic of China under Mao Zadong and the Soviet Union under Nikita Khrushchev. The South, was supported by anti-communist countries, primarily by the United States. The war lasted for 20 years, something the U.S. did not expect.
The US developed a 'domino theory' about Southeast Asia. If one country in the region fell to the Communists, all the rest would too. The Truman policy of 'containment' was developed to prevent the spread of communism. America entered the war in 1959 under President Eisenhower. The war continued with Kennedy and escalated under President Johnson. President Nixon campaigned to end the war and America withdrew in 1973.
Before WWII, Vietnam had been a colony of France (Indochina). During the war, Japan took control of the area. When the war ended there was a power vacuum and Communist leader Ho Chi Minh wanted freedom from European control for the country. After fighting the French, the country was divided by the Communist North led by Ho Chi Minh and the Southern leader Ngo Dihn Diem, who was supported by the US. The country was divided at the 17th parallel.
The Vietnam War can be considered a 'proxy' war in the Cold War. Although the Soviet Union and the United States did not directly go to war, they each supported a different side in the war. The war was very controversial in the United States and 58,220 U.S soldiers lost their lives. The "hippie" movement or counterculture developed out of protests against the war and America's involvement in the war. Millions of Vietnamese died in battle or as civilians caught in the crossfire. America pulled out of the war in March 1973 and South Vietnam fell to the Communists in 1975.