1900s
| Year | American League Champion | National League Champion | World Series Champion |
|---|---|---|---|
| 1900 | Brooklyn Superbas | ||
| 1901 | Chicago White Stockings | Pittsburgh Pirates | |
| 1902 | Philadelphia Athletics | Pittsburgh Pirates | |
| 1903 | Boston Americans | Pittsburgh Pirates | Boston Americans (5-3) |
| 1904 | Boston Americans | New York Giants | Cancelled |
| 1905 | Philadelphia Athletics | New York Giants | New York Giants (4-1) |
| 1906 | Chicago White Sox | Chicago Cubs | Chicago White Sox (4-2) |
| 1907 | Detroit Tigers | Chicago Cubs | Chicago Cubs (4-1) |
| 1908 | Detroit Tigers | Chicago Cubs | Chicago Cubs (4-1) |
| 1909 | Detroit Tigers | Pittsburgh Pirates | Pittsburgh Pirates (4-3) |
Read more about this topic: List Of Major League Baseball Seasons