Founded by Frank and Lester Patrick, The Pacific Coast Hockey Association (PCHA) was a professional men's ice hockey league in western Canada and the western United States. The league merged with the Western Canada Hockey League (WCHL) in 1924. The merged league did not last long, as the WCHL was unable to match the NHL's American expansion and its player salaries.
The league introduced numerous innovations to the sport of ice hockey:
blue lines and goal creases
removed rule that goalies must stay on their feet
The PCHA also developed a farm system for players, and were the first Canadian league to expand into the United States.
While it is debated as to which group instituted the use of jersey numbers in ice hockey, the PCHA is sometimes cited as having been the first.