U.S. military historical joint commands originated in World War II. Mushroom cloud from the nuclear explosion over Nagasaki rising 18 km into the air. ...

President Truman approved the first Unified Command Plan on 14 December 1946. It encompassed the following.

• Alaskan Command
• Atlantic Fleet
• Caribbean Command
• European Command
• Far East Command
• Northeast Command
• Pacific Command

The Atlantic Fleet of the United States Navy is the part of the Navy responsible for operations in around the Atlantic Ocean. ... The Far East Command was a military regional division of the British military. ...

Source

[1] (http://www.shsu.edu/~his_ncp/UCS.html) The Development of Unified Command Structure for the U. S. Armed Forces, 1945-1950. Excerpted from Ronald H. Cole, et al, The History of Unified Command 1946-1993 (Washington, DC: Joint History Office of the Office of the Chairman of the Joint Chiefs of Staff, 1995), pp. 11-21. Retrieved January 2005.