International Association of Professional Base Ball Players

The International Association of Professional Base Ball Players, commonly known as the International Association (IA), was a Canadian-American professional baseball league that operated from 1877 to 1880. For its last two years, it was renamed the National Association (NA), having lost all of its Canadian teams. While generally viewed as inferior to its main rival, the National League, some baseball historians consider the International Association to be a major league.

The IA featured many 19th century baseball stars, including future Hall of FamersCandy Cummings, Pud Galvin, John Montgomery Ward, Mickey Welch, Ned Hanlon, and Bud Fowler. The Syracuse, Buffalo, and Worcester clubs would go on to play in the National League after leaving the IA.