The original South Atlantic League was founded in 1904 by Charles W. Boyer and J.B. Lucy as a Class C league. After a year of dormancy in 1918, it continued at that classification from 1919 to 1920 before being elevated to Class B in 1921. The Great Depression caused the league to shut down from 1931 to 1935, but it returned at Class B from 1936 to 1942. Three more years of dormancy occurred during World War II, but the SALLY League was revived as a Class A circuit from 1946 to 1962.
