The National Association of Base Ball Players (NABBP) was the first organization governing American baseball. The first, 1857 convention of sixteen New York City clubs practically terminated the Knickerbocker era, when that club privately deliberated on the rules of the game. The last convention, with hundreds of members represented only via state associations, provoked the establishment of separate professional and amateur associations in 1871. The succeeding National Association of Professional Base Ball Players is considered the first professional sports league; through 1875 it governed professional baseball and practically set playing rules for all. Because the amateur successor never attracted many members and it convened only a few times, the NABBP is sometimes called "the amateur Association" in contrast to its professional successor.