Which team became the first U.S.-based Stanley Cup champion in 1917?

The Seattle Metropolitans became the first U.S.-based Stanley Cup champion in 1917.

Seattle, the Pacific Coast Hockey Association champion, defeated the defending champion Montreal Canadiens of the National Hockey Association three games to one in a best-of-five series. The Metropolitans won the deciding game 9–1 on March 26, 1917, at Seattle Ice Arena.

The achievement came before the National Hockey League existed; the NHA was replaced by the NHL later in 1917. Seattle’s triumph was also the first Stanley Cup Final played in the United States and the first major professional sports championship won by a Seattle team.

A common mix-up is Portland’s 1916 appearance: the Portland Rosebuds were the first U.S.-based team to reach the Final, but Seattle was the first to win the Cup. The Metropolitans reached the Final again in 1919, but that series was abandoned during the Spanish flu pandemic.