When was the National Associate of Professional Base Ball Players created?

The National Associate of Professional Base Ball Players was created in 1871.

The National Association of Professional Base Ball Players is created. The original teams in the league were: the Boston Red Stockings (Harry Wright‘s new team), the Chicago White Stockings, the Philadelphia Athletics, the New York Mutuals, the Washington Olympics, the Troy (New York) Haymakers, the Fort Wayne (Indiana) Kekiongas, the Cleveland Forest Citys, and the Rockford (Illinois) Forest Citys.