The earliest recorded event in Southport's history was "The Great Swamp Fight" or "Fairfield Swamp Fight" of July 1637 (not to be confused with the later Great Swamp Fight of King Philip's War), an episode of the Pequot War in which English colonial forces led by John Mason and Roger Ludlow vanquished a band of about 80 to 100 Pequot Indians who had earlier fled from their home territory in the Mystic area and had taken refuge with about 200 Sasqua Indians who inhabited the area that is now Fairfield. The exact location of the battle is not known, but it is known to have been in the vicinity of Southport.