In 1920, the American Professional Football Association formed. This organization became the National Football League in 1922. Among its original fourteen teams was the Dayton Triangles. The team formed on August 20, 1920 and played its home games in Dayton, Ohio. The team was named for Triangle Park, where the squad played its home games. The Dayton Triangles defeated the Columbus Panhandles fourteen points to zero on October 3, 1920. This was the first game in the American Professional Football Association. Local businesses, namely Dayton Engineering Laboratories Company, the Dayton Metal Products Company, and the Domestic Engineering Company, sponsored the Dayton Triangles.
The Dayton Triangles remained in the American Professional Football Association and then the National Football League for ten seasons (1920-1929). The Triangles finished the 1920 season ranked sixth in the league. It never finished higher than seventh in its remaining nine seasons. In the 1925, 1928, and the 1929 seasons, the Triangles failed to win a single game, and the team won only one game in the 1923, 1926, and 1927 seasons. At the end of the 1929 season, a group of investors in Brooklyn, New York, purchased the team and moved the squad, now known as the Brooklyn Dodgers, to Brooklyn beginning in the 1930 season.