[9] In about August 1945, the squadron began operations from Key West, Florida, as part of the U.S. Atlantic Fleet.

On 23 April 1947, the former German USS U-3008 reported for duty at Key West with Submarine Squadron 4 and began working with the Operational Development Force.

That duty involved the development of submarine and antisubmarine tactics and lasted until October 1947 when she returned to New London.

This was in reference to Francis Marion, an American Revolutionary War general nicknamed the Swamp Fox.

The Base Realignment and Closure Commission announced on 26 February 1993 that the Charleston Naval Shipyard would be closed.

The squadron was deactivated in late 1995 just prior to the official closure of Charleston Naval Shipyard on 1 April 1996.