History of the National Hockey League (1917–1942)

The National Hockey League (NHL) was founded in 1917 following the demise of its predecessor league, the National Hockey Association (NHA). In an effort to remove Eddie Livingstone as owner of the Toronto Blueshirts, a majority of the NHA franchises (the Montreal Canadiens, Montreal Wanderers, Ottawa Senators and Quebec Bulldogs) suspended the NHA and formed the new NHL. The Quebec Bulldogs, while a member, did not operate in the NHL for the first two years.

Source: Wikipedia — History of the National Hockey League (1917–1942) (CC BY-SA 4.0)