In the history of North American major professional sports league championships (which include the NFL, MLB, NBA, and NHL) a city/metropolitan area has been home to multiple championships in a season fifteen times, most recently in 2018-2019, when the Boston Red Sox and Patriots won their respective leagues, in October 2018 and February 2019. Only Detroit has been host to more than two major league championship teams in a season,^[1] although in 2002 Los Angeles metropolitan area's Lakers and Angels won the NBA and MLB championships along with two other local teams of smaller leagues (the Sparks of the WNBA and the Galaxy of the MLS).

Super Bowls take place in the February after the NFL's regular season. The Super Bowl used to be in January. Therefore, Super Bowl I—which took place January 15, 1967—is officially the championship game for the 1966 season. In the calendar year 2009, Pittsburgh's Steelers and Penguins won their respective championships, but the Steelers' championship was for the NFL's 2008 regular season. However, before 1965, the NFL championship game was played in December of that calendar year. That being said, both of those seasons started in 2008 and ended in 2009. Therefore, Pittsburgh was, until February 2019, in fact the most recent city to win multiple championships in the same season. The Boston Red Sox won the World Series in 2004 and 2018 and the New England Patriots won the Super Bowl in 2004 and 2018 seasons, making the greater Boston area the most recent. On the other hand, Super Bowl III, won by the New York Jets of the AFL on January 12, 1969, is counted towards the 1968 season, disqualifying consideration of 3 titles in New York City in 1969.

All four of Philadelphia's major professional sports teams played in the championship game or series, in their respective sports, following the 1980 season: The 1980 Philadelphia Phillies won the World Series, while the 1980 Philadelphia Eagles lost Super Bowl XV, the 1979-80 Philadelphia 76ers lost the NBA Finals, and the 1979-80 Philadelphia Flyers lost the Stanley Cup Finals.