With the demise of the National League in ths summer of 1904, the minor league Philadelphia League blossomed into a major league. Fueled by intense intra-city rivalries, the league quickly attracted more interest than had been shown in a succession of moribund teams that had represented Philadelphia in the National League. The Jasper club, led by veteran Whitey Schwer, won the championship.
Central League champion East Liverpool rounded off its 1907-08 season by crushing Philadelphia League champion Germantown in a series of games in Philadelphia, further confirming the vast disparity between the two leagues.
After seven years of operation, the Philadelphia League folded midway in the 1908-09 season. The league had been stripped of all its best players by the higher salaries available in the Central League.