In the late 19th century the baseball color line developed in professional baseball, excluding African Americans from league play. In 1885, the Cuban Giants formed the first black professional baseball team. The first league, the National Colored Base Ball League, was organized strictly as a minor league but failed in 1887 after only two weeks owing to low attendance. After several decades of mostly independent play by a variety of teams, in 1920 the first Negro National League was formed and ultimately seven major leagues existed at various times over the next thirty years. After integration, the quality of the Negro leagues slowly deteriorated and the Negro American League of 1951 is generally considered the last major league season. The last professional club, the Indianapolis Clowns, operated as a humorous sideshow rather than competitively from the mid-1960s to the 1980s. (Source: Wikipedia)