Between 1857 and 1899 there has been eight Leagues that Major-Leagues.com is tracking. The table below lists those Leagues and sorts them according to Age, then First Year of play.
Each link goes to a League Page where you can find more information and individual season standings.
| League | Classification | First Year | Age |
|---|---|---|---|
| National League | Major League | 1876 to now | 147 years old |
| American League (plus Western League predecessor) | Major League (plus Elite League predecessor) | 1894 to now (WL+AL) 1901 to now (AL) | 129 years old 122 years old |
| National Association of Base Ball Players | Proto-League | 1857 to 1870 | 14 years old |
| American Association | Rival League | 1882 to 1891 | 10 years old |
| National Association of Professional Base Ball Players | Elite League | 1870 to 1875 | 5 years old |
| League Alliance | Rival League | 1882 | 1 year old |
| Union Association | Rival League | 1884 | 1 year old |
| Players League | Rival League | 1890 | 1 year old |
Major-Leagues.com will be expanding this table as more standings are added.