The National Hockey League was organized on November 26, 1917, in Montréal following the suspension of operations by the National Hockey Association of Canada Limited (NHA). The Montréal Canadiens, Montreal Wanderers, Ottawa Senators and Quebec Bulldogs attended the founding meeting. The Toronto Arenas later were admitted as a fifth team; Quebec decided not to operate during the first season and its players were allocated to the remaining four teams. The first NHL games were played on December 19, 1917.

The NHL expanded to the United States for the first time, with the Boston Bruins making their League debut in 1925-26. The Chicago Black Hawks, Detroit Cougars (later Red Wings) and New York Rangers joined the following season.

The "Original Six" era began its quarter-century run, with the NHL comprised of six teams - the Boston Bruins, Chicago Black Hawks, Detroit Red Wings, Montréal Canadiens, New York Rangers and Toronto Maple Leafs - each season from 1942-43 through 1966-67.

The NHL doubled in size in 1967-68 with six new teams: the California Seals, Los Angeles Kings, Minnesota North Stars, Philadelphia Flyers, Pittsburgh Penguins and St. Louis Blues. The new teams formed the West Division, while the "Original Six" made up the East Division.

Having started the decade with 12 teams, the NHL concluded the 1970s with 21. The addition of nine teams was the most in League history for a single decade.

The NHL again dramatically expanded its footprint across North America. The San Jose Sharks became the NHL's 22nd team in 1991-92 and the decade ended with a four-team expansion over three seasons that increased League membership to 30 teams in 2000-01. Gary Bettman began his NHL tenure as the first Commissioner in League history in February 1993.

Reflecting the growth of its international player base, the NHL expanded its outreach overseas, playing regular-season games in the Czech Republic, Finland, Germany, Great Britain, Japan and Sweden.

The NHL's first regular-season outdoor game, on November 22, 2003, attracted a sellout of 57,167 to Edmonton's Commonwealth Stadium. Four years later, 71,217 fans filled Buffalo's Ralph Wilson Stadium on January 1, 2008, for the inaugural Winter Classic, the League's first outdoor game in the United States. Building on the phenomenal success of these games, the NHL has staged more than 30 outdoor games in the ensuing years at some of the sports world's most iconic football, baseball and soccer venues.

The NHL has grown to 32 teams, adding the Vegas Golden Knights in 2017-18 and Seattle Kraken in 2021-22.

Go to Records.NHL.com to learn more about the history of the NHL.