1977 Major League Baseball expansion

Seattle and Toronto were included in a list of potential expansion cities in a survey conducted by the American League in 1960. The others were Atlanta, Buffalo, Dallas–Fort Worth, Denver, Oakland, and San Diego.

In the 1969 Major League Baseball expansion, Kansas City, Montreal, San Diego, and Seattle were each granted a franchise; the Kansas City Royals and Seattle Pilots were added to the American League, while the Montreal Expos and San Diego Padres joined the National League. The Seattle Pilots only played one season, during which they faced financial difficulties owing to no television coverage, a poorly performing team, a stadium with problems, and the highest ticket and concession prices in the league. Owners of other American League teams wanted Dewey Soriano and William R. Daley to sell the team to a Seattle owner who would improve the team and address issues at Sick's Stadium, particularly uncovered seats with bad views. After several attempts to sell the team to a Seattle owner failed, on 1 April 1970 judge Sidney Volinn declared the team officially bankrupt; it was sold to Bud Selig, who moved the team to Milwaukee and renamed it the Milwaukee Brewers. Selig had negotiated a deal for the purchase with Soriano during Game 1 of the 1969 World Series.