The Packers are the last vestige of "small town teams" common in the NFL during the 1920s and 1930s. Founded in 1919 by Earl "Curly" Lambeau and George Whitney Calhoun, the franchise traces its lineage to other semi-professional teams in Green Bay dating back to 1896. In 1919 and 1920, the Packers competed against other semi-pro clubs from around Wisconsin and the Midwest. They joined the American Professional Football Association (APFA), the forerunner of today's NFL, in 1921. Although Green Bay is by far the smallest professional sports market in North America, its local fan and media base extends 120 miles south into Milwaukee, where it played selected home games between 1933 and 1994.
The Packers have won 13 league championships, the most in NFL history, including nine NFL titles prior to the Super Bowl era and four Super Bowl victories—in 1967 (Super Bowl I), 1968 (Super Bowl II), 1997 (Super Bowl XXXI) and 2011 (Super Bowl XLV). The team is long-standing adversaries of the Chicago Bears, Minnesota Vikings and Detroit Lions, who together comprise the NFL's NFC North division. The Bears–Packers rivalry is one of the oldest in NFL history, dating back to 1921.