The Vietnam War was fought at varying levels of intensity from 1954, after the French were driven out of the country, right up to April 1975. In it, the US supported the South Vietnamese government, which was closer to the West, while the Soviet Union and China supported North Vietnam, which wanted to unify the country under a communist regime.

Estimates of how many Vietnamese soldiers and civilians were killed in the war range from just under 1 million to more than 3 million. More than 58,000 US service members were killed, along with around 5,000 soldiers from allied nations who fought alongside them.

Most US troops had been withdrawn by 1973 and in April 1975, South Vietnam fell to an invasion by North Vietnam. The country was then unified under communist rule.