Congressional Research Service, Library of Congress Washington United States
United States Southern Command SOUTHCOM, headquartered in Miami, FL, was officially established in 1963. Prior to that, U.S. military elements in the Western hemisphere had been organized under the U.S. Caribbean Defense Command. SOUTHCOMs area of responsibility AOR begins at the southern Mexican border and contains the remaining elements of Central and South America, adjacent Atlantic and Pacific waters, as well as the Caribbean Sea, ultimately encompassing 31 countries and 16 dependencies and areas of special sovereignty. The region represents about one-sixth of the landmass of the world assigned to regional unified commands.