History of organizational changes in the NHL

Since being founded in 1917, the National Hockey League (NHL), which in its first two seasons started out as a three-team league and eventually grew to thirty-one in its current state, has expanded and contracted numerous times throughout its history. The following is a complete history of organizational changes in the NHL.

The four teams that began the inaugural NHL season were the Montreal Canadiens, the Montreal Wanderers, the original Ottawa Senators, and the Toronto Arenas. However, after completing four games out of the scheduled 22, the Wanderers withdrew from the league due to their arena burning down, and the NHL continued this season and the next with only three teams.

In its third season, 1919–20, the NHL underwent its first expansion, adding the Quebec Bulldogs. Toronto changed its name to Toronto St. Patricks. The next season, however, Quebec relocated to Hamilton, becoming the Hamilton Tigers. These same four teams continued playing for four seasons, up to 1923–24.

Two new teams joined the NHL in its eighth season, the Boston Bruins and the Montreal Maroons.

The next season, the NHL added another new team, the Pittsburgh Pirates, and relocated the Hamilton Tigers to New York as the New York Americans.

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