South Korea played an important role in the Vietnam War (1964-1975). After the United States withdrew its forces in 1973, South Korea sent its own troops to help the South Vietnamese government. The Republic of Korea (ROK) Army Expeditionary Force provided military assistance and support to South Vietnam, with a total of 320,000 troops taking part in the war effort.

The ROK forces were mostly stationed in the Central Highlands and along the Ho Chi Minh Trail. They provided security for local Vietnamese citizens and helped the South Vietnamese military to protect their borders. In addition, South Korean forces built infrastructure for development projects, including roads, bridges, irrigation systems and airfields.

The presence of Korean troops in Vietnam was controversial, with some accusing them of human rights abuses. However, they were credited with providing much-needed assistance to the South Vietnamese government during a difficult period in its history. The Korean Army was withdrawn from Vietnam in 1978 and their contribution to the war effort has been largely forgotten in history.