A well-traveled franchise, playing in Philadelphia, Kansas City, and Oakland, the Athletics have been a team of tremendous peaks and dark valleys.

Four times they have produced great dynasties, but they have also finished last 30 times in 100 AL seasons. This franchise is commonly known as the A's, earlier also known as the Mack-Men, in tribute to their long-time owner and field manager Connie Mack. Faced with financial hardships (as he so often was), Mack sold most of his stars in the mid-Teens, resulting in seven straight last place finishes from 1915-1921. In 1916 they lost 117 games. In the 1920s the A's had to catch up with Babe Ruth and the Yankees, and by 1925 they were in position to do so. One of the greatest teams of all-time, the A's won three straight pennants from 1929-1931, earning the World title the first two seasons. This was accomplished despite the presence of the Yankees great Ruth/Lou Gehrig team.

Jimmie Dykes took over as manager after Mack's retirement in 1951, and by 1955 new ownership moved the team to Kansas City. The A's tried eleven managers in Kansas City, with 74 wins the most they could muster in a single season. New owner Charlie Finley switched the team to Oakland for the 1968 season. United by their common hatred for Finley, the "Mustache Gang" became just the second team (in addition to the Yankees) to win three straight World Series, from 1972-1974. Each series was a test of the team's pitching and defense, which it was built upon. In 1975 they failed to add a fourth consecutive title, losing to the Red Sox in the playoffs, and the dynasty was over.

In the early 1980s Billy Martin led the A's back into the playoffs with a division title in 1981 built around the efforts of Rickey Henderson, Tony Armas, Mike Norris and Rick Langford. That team burned out quickly and the rest of the 1980s was spent rebuilding. New ownership installed former White Sox manager Tony LaRussa at the helm of the A's in 1987. The next year he guided them to the World Series and they would return in 1989 and 1990. LaRussa's A's were built around power - provided by Jose Canseco, Mark McGwire, Dave Henderson and Dave Parker. The team also boasted pitching stars Dave Stewart and Dennis Eckersley - the best stopper in baseball.

The 1988-1990 A's proved less successful in the post-season than the 1970s Finley A's, losing the World Series in 1988 and 1990, despite being favored. The 1990 sweep at the hands of the Reds was especially embarrassing. In 1989 the A's defeated the Giants in one of the most memorable Series ever, which was marred by the San Francisco earthquake. LaRussa stayed until 1995, adding a division title in 1992. In 1999 Art Howe steered the team to a second place finish, and followed in 2000 with an AL West title, behind sluggers Jason Giambi, Matt Stairs and Ben Grieve. In the post-season they pushed the World Champion Yankees to five games before losing.

The 2002 season proved to be an amazing story for the A's, who used their recent recipe for success once again. After a mediocre first-half, the team rolled to behind shortstop Miguel Tejada, and pitchers Barry Zito, Mark Mulder and Tim Hudson, to a 103-win season on the strength of an American League record 20 consecutive wins in August/September. Despite the constant winning, Oakland could not shake the pesky Angels, who came back to regain the AL West lead after the streak ended. But the A's regrouped and held off Anaheim to win their 12th AL West title.

However, it was the same old story in the playoffs, as they again lost in game five, this time to the underdog Minnesota Twins.

In 2004 the Oakland Athletics finished in 2nd place in the American League East Division with a 91-71 record.

In 2006 the Athletics finished in 1st place with a 93-69 record. They lost in the 2nd round of the playoffs to the Tigers.