The **National League (NL)** is the oldest existing major professional baseball league in the United States, founded in 1876 as the National League of Professional Baseball Clubs to replace the earlier National Association of Professional Base Ball Players. It is one of two leagues that make up Major League Baseball (MLB), the other being the American League, which was established 25 years later. The NL is often called the "Senior Circuit" to distinguish it from the American League's "Junior Circuit" status[1][2]. The National League initially faced competition from several rival leagues, most notably the American Association in the late 19th century, but eventually emerged dominant. In 1903, the NL and AL agreed to recognize each other as major leagues and began the tradition of competing in the World Series, an annual championship series that continues today. The NL has 15 teams divided into three divisions: East, Central, and West. Notable franchises include the Atlanta Braves, Chicago Cubs, Los Angeles Dodgers, and St. Louis Cardinals. The Cardinals hold the record for the most World Series titles among NL teams, with 11 championships, followed by the Dodgers and Giants[1][2]. The NL has played a pivotal role in shaping professional baseball, contributing to the sport's growth into a major American cultural institution. Its teams have won 53 of the 121 World Series contested through 2025, reflecting a rich legacy of competitive success[2]. The league operates under MLB governance, which merged the NL and AL administrative functions in 2000. MLB, including the NL, is a major player in sports entertainment, with extensive media coverage and a large fan base across North America[3]. In summary, the National League is a cornerstone of professional baseball history, known for its longevity, historic franchises, and significant contributions to the sport's development and popularity. It remains a vital part of MLB's structure and the broader cultural fabric of North American sports[1][2][3].