Original Six era

The Original Six is the group of six teams that made up the National Hockey League (NHL) for the 25 seasons between the 1942–43 season and the 1967 NHL expansion. These six teams are the Boston Bruins, Chicago Black Hawks, Detroit Red Wings, Montreal Canadiens, New York Rangers, and the Toronto Maple Leafs, all of which are still active franchises in the league.

Of the Original Six, only the Toronto Maple Leafs have not advanced to the Stanley Cup Finals since the expansion, while the other five have appeared in at least three Finals since 1967 and have each won a championship at least once during the most recent 25 seasons (Toronto last won the Stanley Cup during the 1966–67 season when a team only had to win two rounds to secure the title).

The term was not used during the era, having originated after 1967 expansion. Only Montreal and Toronto are actual original charter members of the NHL in 1917, but all six joined the NHL in the league's first decade, and are commonly considered as a traditional set.

The NHL consisted of ten teams during the 1920s, but the league experienced a period of retrenchment during the Great Depression, losing the Pittsburgh Pirates/Philadelphia Quakers, Ottawa Senators/St. Louis Eagles, and Montreal Maroons in succession to financial pressures. The New York/Brooklyn Americans – one of the league's original expansion franchises, along with the Bruins and Maroons – lasted longer, but played as wards of the league from 1936 onward. World War II and its own economic strains severely depleted the league's Canadian player base, since Canada entered the war in September 1939 and many players left for military service. The Americans suspended operations in the fall of 1942, leaving the NHL with just six teams.

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