What NHL team won the Stanley Cup in 1918, the league's first season?

The Toronto Arenas won the Stanley Cup in 1918, the first season of the National Hockey League.

Toronto defeated the Vancouver Millionaires of the Pacific Coast Hockey Association three games to two in a best-of-five championship series played from March 20 to 30, 1918. The final was held entirely at Toronto's Arena Gardens because the series alternated between the leagues' home rules and venues.

The team-name history creates a common source of confusion. Toronto's NHL club had no official nickname during that season and was often called the Torontos or associated with the earlier Blueshirts. “Toronto Arenas” is the conventional retrospective name, reflecting the Arena Gardens ownership; the name Toronto Arenas became official after the season.

Toronto's victory was also the first Stanley Cup championship by an NHL team and the first major professional sports title won by a Toronto-based team. The franchise later became the Toronto Maple Leafs.