All-American Girls Professional Baseball League

The All-American Girls Professional Baseball League (AAGPBL) was a professional women's baseball league founded by Philip K. Wrigley, which existed from 1943 to 1954. The AAGPBL is the forerunner of women's professional league sports in the United States. Over 600 women played in the league, which eventually consisted of 10 teams located in the American Midwest.

With the entry of the United States into World War II, several major league baseball executives started a new professional league with women players in order to maintain baseball in the public eye while the majority of able men were away. The founders included Philip K. Wrigley, Branch Rickey and Paul V. Harper. Like the male major league, the 'girls' league was also informally segregated; thus, no African Americans were recruited or hired.

As attendance and revenues began to fall in the early 1950s, the league became less alluring to players, and some even returned to playing softball. Teams rapidly began to close down operations each year until, at the end of the 1954 season, only five teams remained, and the AAGPBL officially shut down and closed in 1954.