American League pennant winners 1901-68

Each season, one American League (AL) team wins the pennant, signifying that they are the league's champion and have the right to play in the World Series against the champion of the National League. The pennant was presented to the team with the best win–loss record each year through the 1968 season, after which the American League Championship Series (ALCS) was introduced to decide the pennant winner. The first modern World Series was played in 1903 and, after a hiatus in 1904, has taken place in every season since except 1994, when a players' strike forced the cancellation of the postseason. The current American League pennant holders are the Cleveland Indians who won in October 2016.

In 1969, the league split into two divisions, and the teams with the best records in each division played one another in the five-game ALCS to determine the pennant winner, who received (and continues to receive) the William Harridge Trophy. The trophy features a golden eagle, the league's emblem, sitting atop a silver baseball and clutching the American League banner. The trophy is named for Will Harridge, who was league president from 1931 to 1958. The format of the ALCS was changed from a best-of-five to a best-of-seven format in the 1985 postseason. In 1995, an additional playoff series was added when Major League Baseball restructured into three divisions in each league. As of 2010^[update], the winners of the Eastern, Central, and Western Divisions, as well as the AL Wild Card winner, play in the American League Division Series, a best-of-five playoff to determine the opponents who will play in the ALCS. American League pennant winners have gone on to win the World Series 64 times, most recently in 2015.

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