Beginning in May 1882 and continuing for a full decade, the Association became a significant force in the early development of Major League baseball. Unlike the National League, the American Association played on Sundays and allowed the consumption of alcohol at all games. With breweries among its most ardent backers, the American Association became known as "The Beer and Whiskey League." The policy seriously affected the revenue for many struggling NL teams and became a key stimulus for organizing the American Association.
In its ten years of existence, the Association challenged the National League for dominance of professional baseball. In seven of those ten years, the American Association and the National League participated in an early version of the World Series. Of those seven post season encounters, the American Association won only once.
During its ten-year struggle to survive, the AA fielded some two dozen different teams. It occasionally lost players to the traditionally stronger NL. But perhaps the most serious blow that led to the demise of the AA was the siphoning of the Association's talent by the Players' League, a third major league formed in 1890.