Roscommon entered the championship as defending champions, however, they were defeated in the Connacht Championship.
On 22 September 1940, Louth won the championship following a 5–05 to 2–07 defeat of Mayo in the All-Ireland final. They led by 3–01 to 1–05 at half-time. This was Louth's second All-Ireland title and their first in four championship seasons.[1]