This is a list of seasons of the National Hockey League (NHL), a professional ice hockey league, since its inception in 1917. The list also includes the seasons of the National Hockey Association (NHA), the predecessor organization of the NHL, which had several teams that would continue play in the NHL. Only two franchises, the Montreal Canadiens and Toronto Maple Leafs (formerly the Arenas and St. Patricks), still exist from the founding of the league. The Quebec Bulldogs, which suspended after the last NHA season, returned to play in the third NHL season, although they were considered founding members of the NHL. The league would move the team to Hamilton in 1920 and dissolve the team in 1925. The original Ottawa Senators would continue in the league until 1935, where, after one season in St. Louis as the St. Louis Eagles, the franchise was dissolved by the league. The current Ottawa Senators franchise does recognize the history of the original Senators (through retired numbers and a heritage jersey).The list is sub-divided using the same eras as the series of articles on the history of the National Hockey League.