The U.S. Army's 5th Special Forces Group (Airborne) departs South Vietnam. The Special Forces were formed to organize and train guerrilla bands behind enemy lines. President John F. Kennedy, a strong believer in the potential of the Special Forces in counterinsurgency operations, had visited the Special Warfare Center at Fort Bragg to review the program and authorized the Special Forces to wear the headgear that became their symbol, the Green Beret.
The 5th Group was sent to Vietnam in October 1964 to assume control of all Special Forces operations in Vietnam. Prior to this time, Green Berets had been assigned to Vietnam only on temporary duty. The primary function of the Green Berets in Vietnam was to organize the Civilian Irregular Defense Groups (CIDG) among South Vietnam's Montagnard population. The Montagnards—"mountain people" or "mountaineers"—were a group of indigenous people from several tribes, such as the Rhade, Bru, and Jarai, who lived mainly in the highland areas of Vietnam. These tribes were recruited to guard camps in the mountainous border areas against North Vietnamese infiltration. At the height of the war the Green Berets oversaw 84 CIDG camps with more than 42,000 CIDG strike forces and local militia units. The CIDG program ended in December 1970 with the transfer of troops and mission to the South Vietnamese Border Ranger Command. The Green Berets were withdrawn as part of the U.S. troop reductions in Vietnam.