"Tessie" is both the longtime anthem of the Boston Red Sox and a 2004 song by the punk rock group Dropkick Murphys. The original "Tessie" was from the 1902 Broadway musical The Silver Slipper. The newer song, written in 2004, recounts how the singing of the original "Tessie" by the Royal Rooters fan club helped the Boston Americans win the first World Series in 1903. The name Tessie itself is a diminutive form used with several names, including Esther, Tess, and Theresa/Teresa.
The original version of "Tessie (You Are the Only, Only, Only)" was written by Will R. Anderson and was featured in the Broadway musical The Silver Slipper, which ran for 160 performances between October 27, 1902 and March 14, 1903. The song was about a woman singing to her beloved parakeet "Tessie".
While a popular tune, the song gained greater notoriety when it was adopted as a rallying cry by the Royal Rooters, a collection of loyal fans led by Michael T. McGreevy, informally known as "Nuf Ced" McGreevy, owner of the 3rd Base saloon. McGreevy earned his nickname "Nuf Ced" due to the way he kept peace in his bar: when he grew frustrated with arguments over the Boston Americans (who would later be renamed the Red Sox) and the Boston Braves (who would later move to Milwaukee and, eventually, Atlanta), he would pound his hand on the bar and declare "'Nuff [enough] said!". Boston mayor John "Honey Fitz" Fitzgerald, grandfather of President John F. Kennedy, was a member of the Royal Rooters.
After the first four games of the 1903 World Series, Boston was down 1-3 to the Pittsburgh Pirates. (It was a best-of-nine series; five wins were needed to win the series.) The Royal Rooters began rallying their team with every song they could think of; ultimately "Tessie" helped win the day. There are stories that the Royal Rooters actually traveled to Pittsburgh and hired a band to play "Tessie" to annoy the Pirates on their home field. Pittsburgh outfielder Tommy Leach credited at least part of Boston's win to "that damn 'Tessie' song." He continued: "It was a real hum-dinger of a song, but it sort of got on your nerves after a while."