Which major league is nicknamed the Senior Circuit?

Which major league is nicknamed the Senior Circuit? The answer is the National League.

The National League is the older of Major League Baseball’s two current leagues. It was founded in 1876, five years before the American League, which explains the nickname “Senior Circuit.” The American League is commonly called the “Junior Circuit.”

The National League originally operated as a separate professional league, with its champion determined through regular-season standings. It later became part of the modern MLB structure after the American League was established in 1901. The two leagues eventually met in the World Series and became more closely integrated.

A frequent confusion is the Federal League, another short-lived major league that operated from 1914 to 1915. The Pacific Coast League was historically important but is not MLB’s senior league. Since 2022, the National League has used the designated hitter in every game, ending the league’s long-running pitcher-batting tradition.