The National Hockey League began with five Canadian teams after the National Hockey Association was disbanded in 1917. Six teams were in the league from 1942 to 1967. The NHL expanded to 12 teams in 1967 and has grown to 30 teams as of the 2015 season.
The NHL moved into the United States in 1924 with the formation of the Boston Bruins. The next American club was the New York Rangers in 1926.
The NHL gained national coverage in Canada when Foster Hewitt began broadcasting games for the Canadian Broadcasting Corp. in 1933. Hewitt also was the announcer when the CBC began its Saturday-night "Hockey Night in Canada" telecasts in 1952.
The term "Original Six" began in 1942 after the Great Depression and World War II reduced the league to six teams. The clubs were in Montreal, Toronto, New York, Boston, Detroit and Chicago; the group remained intact until 1967.
The first American-born player to be considered an NHL star was Hockey Hall of Famer Frank Brimsek, who played 10 seasons in Boston and Chicago between 1938 and 1950. Another Hall of Fame member, Willie O'Ree, was the first black NHL player when he played for Boston in 1958.
The NHL doubled in size, to 12 teams, and stretched to the West Coast with teams in Vancouver, Los Angeles and Oakland, in 1967. Another six teams were added by 1974, then four more in 1979 when the World Hockey Association merged with the NHL. The NHL reached its current 30-team size in 2000 with the introduction of the Minnesota Wild and Columbus Blue Jackets.