The Pacific Coast Hockey Association was a professional ice hockey league in western Canada, operating from 1911 to 1924 when it merged with the Western Canada Hockey League. During this time, the PCHL was considered to be one of the major leagues of hockey.
The PCHA was founded by Frank Patrick and Lester Patrick with three teams: the New Westminster Royals, the Victoria Aristocrats, and the Vancouver Millionaires. Although they did not challenge for the Stanley Cup the first year, the defeat of the 1913 Stanley Cup champion Quebec Bulldogs in an exhibition series (it would have been an official series had the Bulldogs decided to put the Cup on the line) by the Aristocrats gave the league a good deal of status. An agreement between the National Hockey Association and the PCHA was made in 1915 where the two league champions would face each other for the Stanley Cup. That year also saw the first Stanley Cup champions from the PCHA, when the Millionaires defeated the Ottawa Senators in a best-of-five series.
1916 saw the first American team, the Portland Rosebuds (formerly the Royals) playing for the Stanley Cup, while the Seattle Metropolitans was the first American team to win the Stanley Cup the following year.
In 1921, the Western Canada Hockey League, another western major league of hockey, was formed, and the Stanley Cup playoffs was modified to include teams from the WCHL. The following two years, which would turn out to be the last two years of the PCHA, the league played interleague games with the WCHL. Interestingly, the last year of the PCHA had the three remaining teams all finish with under-.500 records.
In 1924, the Vancouver Maroons folded, and the two remaining teams joined the Western Hockey League (formerly the WCHL), ending the life of the PCHA. The Victoria Cougars would win the Stanley Cup in 1925, but this win would be the last by a non-NHL team, and the last by a team from the west for a long time.
This new league would also not last long, as the WHL were unable to match the NHL's American expansion and their player salaries, which led the Patrick brothers to sell players or, in the case of the Portland Rosebuds (not to be confused with the Rosebuds of the PCHA) and the Victoria Cougars, the team itself. The Rosebuds would become the present-day Chicago Blackhawks, while the Cougars became the modern-day Detroit Red Wings.
List of Pacific Coast Hockey Association Champions
Internet Hockey Database (http://www.hockeydb.com/ihdb/stats/leagues/pcha1918.html) - standings and statistics