The rise of organized baseball after the Civil War led to early attempts to segregate the sport. The National Association of Amateur Base Ball Players rejected African-American membership in 1867, and in 1876, owners of the professional National League adopted a “gentleman’s agreement” to keep blacks out. Subsequent African American players found their greatest opportunities with traveling teams until 1920, when Rube Foster launched the Negro National League. Reformulated several times with new leagues and owners, Negro League baseball enjoyed periods of success in the early1920s and again after the Great Depression. However, Jackie Robinson’s integration of baseball in 1947 prompted a slow but irreversible influx of talent to the majors, and the remaining Negro League teams generally folded by the 1960s.