Prior to the first season of the National Hockey League (NHL), which commenced on December 19, 1917, there had been many seasons of ice hockey played by various amateur and professional leagues, often held contemporaneously, going back to the 1880s, to which the NHL can trace its roots. Below is a list of pre-NHL seasons by ice hockey leagues that are precursors of the National Hockey League.
The Montreal Winter Carnival ice hockey tournaments (MWCT) were a series of annual tournaments held in the 1880s in conjunction with the Montreal Winter Carnival, in Montreal, Quebec, Canada. First held in 1883, these tournaments are considered to be the first championship ice hockey tournaments and the predecessor to the first championship ice hockey league, the Amateur Hockey Association of Canada.
The Western Canada Hockey League (WCHL) existed from 1921 to 1926. While the WCHL wasn't a pre-NHL league, it is generally deemed by hockey historians to have been a major league. Two years prior to its folding, the PCHA merged with it. The last season, 1925–26, it had been renamed the Western Hockey League because one of its teams had moved to the United States. The NHL would buy the rights to the WHL players as part of its disbanding.
Prior to 1905 (FAHL), 1910 (NHA) and 1912 (PCHA) league play started in January and ended in March of one calendar year.