| Founded | February 2 1876 |
|---|---|
| No. of Teams | 15 |
| Recent Champion | To be decided between Los Angeles Dodgers or New York Mets (2024) |
| Most Titles | Los Angeles Dodgers (24) |
Founded on February 2, 1876, to replace the National Association of Professional Base Ball Players (NAPBBP) of 1871–1875 (often called simply the "National Association"), the NL is sometimes called the Senior Circuit, in contrast to MLB's other league, the American League, which was founded 25 years later and is called the "Junior Circuit". Both leagues currently have 15 teams.
The National League survived competition from various other professional baseball leagues during the late 1800s. Most did not last for more than a few seasons, with a handful of teams joining the NL once their leagues folded. The American League declared itself a second major league in 1901, and AL and NL engaged in a "baseball war" during the 1901 and 1902 before agreeing to a "peace pact" that recognized each other as legitimate "major leagues". As part of this agreement, the leagues agreed to respect player contracts, establish rules about relationships with minor league clubs, and allow their champions to meet in a "World Series" to decide the overall professional baseball championship. National League teams have won 51 of the 118 World Series championships contested from 1903 to 2022.
For decades, Major League baseball clubs only played teams from their own league during the regular season and most of the playoffs, with only their champions facing off in the World Series. This separation gradually caused the leagues to develop slightly different strategies and styles of play. The National League was long considered the more "traditional" league, a reputation most exemplified by the NL's more prevalent use of "smallball" tactics and lack of a designated hitter rule, which the AL implemented in 1973. However, with the advent of free agency in the 1970s allowing for more player movement between leagues, the introduction of regular season interleague play in 1997, and the NL's adoption of the designated hitter rule in 2022, the difference in play between the two major leagues has diminished considerably.
Though both leagues agreed to be jointly governed by a commissioner in 1920, they remained separate legal and business entities with their own president and management. This was the case until after the 1999 season, when the National League legally merged with the American League under the auspices of Major League Baseball, which now operates much like other North American professional sports leagues, albeit with two "leagues" instead of "conferences".
