One of the American League's eight charter franchises, the club was founded in Buffalo, New York in 1901. After the move from Buffalo to Boston they were a dominant team, defeating the Pittsburgh Pirates in the first World Series in 1903. They won four more championships by 1918, and then went into one of the longest championship droughts in baseball history. Many attributed the phenomenon to the "Curse of the Bambino," said to have been caused by the sale of Babe Ruth to the New York Yankees in 1920. The drought was ended and the "curse" reversed in 2004, when the team won their sixth World Series Championship.