The South Korean Assembly votes to send 20,000 additional troops to Vietnam to join the 21,000 Republic of Korea (ROK) forces already serving in the war zone. The South Korean contingent was part of the Free World Military Forces, an effort by President Lyndon B. Johnson to enlist allies for the United States and South Vietnam. By securing support from other nations, Johnson hoped to build an international consensus behind his policies in Vietnam. The effort was also known as the "many flags" program.
South Korean forces had been in South Vietnam since August 1964, when Seoul sent a liaison unit to Saigon. The first contingent was followed in February 1965 by engineer units and a mobile hospital. Although initially assigned to non-combat duties, they came under fire on April 3. In September 1965, in response to additional pleas from Johnson, the South Korean government greatly expanded its troop commitment to Vietnam and agreed to send combat troops. By the close of 1969, over 47,800 Korean soldiers were actively involved in combat operations in South Vietnam. Seoul began to withdraw its troops in February 1972, following the lead of the United States as it drastically reduced its troop commitment in South Vietnam.