The NHL started with three of the six NHA clubs (Montreal Canadiens, Montreal Wanderers and Ottawa Senators) and a Toronto franchise run by the Toronto Arena Co., which leased the players of the Toronto Blueshirts. Almost immediately after starting the season, the Wanderers folded, leaving three teams to complete the season. The same three teams returned for 1918–19 before Quebec 'returned' for 1919–20, moving to Hamilton the following year. The same four-team configuration lasted until 1924–25 when the Montreal Maroons and the Boston Bruins joined the league. Expansion into other cities followed, lasting until the 1930s, when several teams folded.
