The Philadelphia Athletics were a Major League Baseball team that played in Philadelphia from 1901 to 1954, when they moved to Kansas City, Missouri, and became the Kansas City Athletics. In the early years, the A's established themselves as one of the dominant teams in the new league, winning the A.L. pennant six times (1902, 1905, 1910, 1911, 1913, and 1914), and winning the World Series in 1910, 1911, and 1913.