Even if you don't know the song "Seven Nation Army", then chances are you know the opening 7 notes.
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Anthem was sung by football fans in stadiums across the world.
So, how did the song make it a transformation from an Indie rock staple to a world-wide sports Anthem?
Well, it all began with the Belgians in Italy.
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Then in 2006, an Italian club A.S. Roma played against club Brugge, where the song fascinated the Italian fans and they took it back home to Rome.
The timing was perfect for the Italians, as it became their unofficial anthem for the 2006 FIFA World Cup, as the world took notice of this catchy tune.
A FUN FACT: The song is known as "The Po Po Po Po song" in Italy.
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Even though millions of fans chant together to the opening notes of this song, a large portion of them do not even know the name of this song.
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This is what Jack White, the man behind "Seven Nation Army" had to say about it,
"I especially love that most people have no idea what song the melody they are chanting came from. The fewer people know where it came from, the more it is integrated into the tradition of folk music, and the more it feels anonymous to the public, the more I'm fulfilled as a songwriter."