Current rules require overtime for playoff games that are tied after regulation, however that was not always the case.
In 1920, the Ottawa Senators were automatically declared the league champion when the team had won both halves of the regular season.
The two halves format was abandoned the next year, and the top two teams faced off for the NHL championship in a two-game total goals series.
As travel expenses were high during these times, it was often the case that the NHL champions were sent west to compete.
[1] With the merger of the PCHA and WCHL in 1925 and the merged league's collapse in 1926, the NHL took de facto control of the Stanley Cup.
The two-game total goals format was abolished in 1937, with those series being changed to best-of-three affairs.