The International Professional Hockey League (IPHL) was the first fully professional Ice hockey league, operating from 1904 to 1907. It was formed by Jack 'Doc' Gibson, a dentist who played hockey throughout Ontario. The IPHL was a five team circuit which included Pittsburgh, Pennsylvania, Sault Ste. Marie, Ontario, Sault Ste. Marie, Michigan, Calumet, Michigan and Houghton. The IPHL was instrumental in changing the nature of top-level senior men's ice hockey from amateur to professional.
The International Hockey League (IHL) attracted some of the best players from established Canadian amateur leagues. With the hockey season only lasting a couple of months a year because teams played on natural ice, most of the players went home to their families and regular jobs in Canada at the end of each season. In many cases, this meant that IHL managers would have to organize completely new teams each season.
After the 1906-07 season, Canada finally established individual professional teams and, soon after, leagues were formed drawing back many players to play for their home crowds. In addition, it was apparent that, while the league was talking about expanding to larger centres such as Toronto, Cleveland and Duluth, there were problems among the existing clubs. On November 4, 1907, citing a lack of players, the IPHL folded.