In 1869, the previously amateur National Association of Base Ball Players, in response to concerns that some teams were paying players, established a professional category. The Cincinnati Red Stockings were the first team to declare their intention to become fully professional. Other teams quickly followed suit. By 1871, several clubs, wanting to separate fully from the amateur association, broke away to found the National Association of Professional Base Ball Players.. In 1876, wanting an even stronger central organization, six clubs from the NA and two independents established the National League: Boston Red Stockings, Hartford, Mutual, Athletic, Chicago, and the St. Louis Brown Stockings from the NA plus independent clubs Louisville and Cincinnati. The NA was the first professional baseball league. Its status as a major league is in dispute. Major League Baseball and the Baseball Hall of Fame do not recognize it as a major league, but the NA comprised most of the professional clubs and the highest caliber of play then in existence. Its players, managers, and umpires are included among the "major leaguers" who define the scope of many encyclopedias and many databases developed by the Society for American Baseball Research or Retrosheet. Several factors limited the lifespan of the National Association including dominance by a single team for most of the league's existence, instability of franchises as several were placed in cities too small to financially support professional baseball, lack of central authority, and suspicions of the influence of gamblers.
Member clubs
Professional baseball clubs in the 19th century were often known by what is now regarded as a "nickname", although it was actually the club's name. This was a practice carried over from the amateur days. The singular form of a "nickname" was often the team name itself, with its base city "understood" and was so listed in the standings; for example the Atlantic Base Ball Club, which was located in Brooklyn. Rather than "Brooklyn Atlantics", the team was simply called "Atlantic", or "Atlantic of Brooklyn" if deemed necessary by the writer. Another common practice was to refer to the team in the plural, hence the "Bostons" the "Chicagos" or the "Mutuals". Frequently sportswriters would apply a creative pseudonym to call the team by in newspaper articles, often using one with something to do with the team colors, such as the Red Stockings or Red Caps, White Stockings, Green Stockings, and Canaries. This practice of using the singular form of the "nickname" as the team name faded with time, although as recently as the early 1900s the team generally known as "Philadelphia Athletics" was shown in the American League standings as the traditional way of "Athletic". That team sported an old-English "A" on its jerseys, as had its nominative predecessors. Later, the Encyclopedia of Baseball attempted to retrofit the names into a modern context. In the following list, the bold names are the names most often used by contemporary newspapers in league standings, and the linked names after them are those typically ascribed to the teams now, using the Encyclopedia of Baseball standard.
Individual statistics from tie games count towards players' career totals, but tie games are excluded when computing winning percentage and games behind.
Eight players that played in the Association have been inducted into the Baseball Hall of Fame, with George Wright being the first NA inductee in 1937 and Deacon White being the most recent in 2013.
