USA

Professional American Football Leagues started with the National Football League (NFL) in 1920.

Rivals to it included numerous Leagues called the American Football League until one in 1960 became a success, which is why the Super Bowl is played – between the winners of the NFL & AFL (now merged – with the two leagues called the National Football Conference & American Football Conference.)

Since then there has been the World Football League (1973-1974), United States Football League (1983-1985) and XFL (2001).

There has been numerous Pro Development Leagues also from the Continental Football League (1965-1969), World League of American Football/ NFL Europe (1991-2007), & United Football League (2009-2012)

Major Leagues (AFL Era):

American Football League | 1926

American Football League 1934

American Football League 1936-1937

American Football League 1938-1939

American Football League 1940-1941

Pacific Coast Pro Football League 1940-1948

American Football League 1944

All-American Football Conference 1946-1949

Rival Major Leagues (Modern Era):

World Football League 1974-1975

XFL 2001