Most people familiar with the U.S. Army Special Forces know that currently (mid-2016) there are five active duty Special Forces groups and two National Guard Special Forces groups. Less well-known are the existence of other Special Forces groups that have long been de-activated.  The 8th Special Forces Group was one of these groups. It was established at Fort Gulick in the Panama Canal Zone in 1963 from a nucleus of Green Berets from the 7th Special Forces. It was de-activated in 1972 – coinciding with the withdrawal of troops from South Vietnam (that war ended in 1975) and the subsequent down-sizing of the U.S. military.
The 8th Special Forces Group formed the nucleus of the Special Action Force (SAF) – Latin America. The SAF included the Special Forces Operational Detachment Alphas (SFODAs), as well as medical, Civil Affairs, military police, military intelligence, Army Security Agency , and Psychological Operations detachments. This SAF organization provided all the necessary assets for the conduct of a large counterinsurgency or unconventional warfare mission or operation. The Special Action Force would later be renamed as the Security Assistance Force.
The mission of the Special Action Force was:
– To advise, train, and assist Latin American military forces in counterinsurgency activities,
– To develop, organize, and equip, train and direct native forces in the conduct of guerrilla warfare,
– To support the U.S. Armed Forces Southern Command contingency plans,
– To assist Southern Command in developing plans to use the Special Action Force under varying conditions,
– To accomplish civic action projects.
The men of the 8th Special Forces Group were responsible for unconventional warfare, counterinsurgency, mobile training team missions, and special operations in the Caribbean, Central America, and South America. Some of the notable missions they took part in were the 1969 ‘Soccer War’ between El Salvador and Honduras and the capture (and killing) of Che Guevara. 
The deactivation of 8th Special Forces Group took place in 1972. The groups’ personnel, facilities, and equipment were transferred to the newly-established 3rd Battalion of the 7th Special Forces Group. This deactivation coincided with the re-structuring of the Special Forces groups to have three line battalions each. While 3rd Battalion of the 7th Special Forces Group remained in Panama until the signing of the Panama Canal Treaty, the remainder of 7th Special Forces Group was based at Fort Bragg, North Carolina. In time, 3/7th would re-locate to Fort Bragg and then eventually move with the entire 7th Special Forces Group to Eglin Air Force Base in Florida.
 Other Special Forces groups that were de-activated include the 6th, 11th, 12th, 16th, and 77th Special Forces Groups. The 6th Special Forces Group was geared towards Africa and the 11th and 12th Special Forces Groups were Army Reserve Groups deactivated in 1994. The 77th preceded the 7th and was based at Fort Bragg. The 16th was a de-activated National Guard Special Forces group.
 The Army Security Agency (ASA) did signals intercept for the U.S. Army and each Special Forces group had an ASA element within its organization.
 Guevara was an Argentinian doctor who participated in the Communist revolution in Cuba who later tried to export his version of Marxist revolutionary warfare to South America – unsuccessfully. He was a cult hero in the United States of the left-wing student anti-war movement during the Vietnam conflict.
Video – Watch a 6-minute U.S. Army video about 8th Special Forces Group conducting High Altitude Low Opening (HALO) parachute training at Fort Gulick, Panama Canal Zone; http://www.youtube.com/watch?v=uCqPFLl1T-g
Flash – The 8th Special Forces Group flash can be viewed at the link below. The flash is the emblem worn on the green beret that Special Forces Soldiers wear. Each group has their own distinctive flash.
Photo of HALO jumper exiting aircraft from U.S. Army video cited under references.
Maps from CIA website.