Suzanne Collins' new Hunger Games books proved so popular, and they were swiftly adapted into a popular series of blockbusters.

The final book, Mockingjay, introduced a song called "The Hanging Tree." American composer James Newton Howard turned Collins' lyrics into an actual song for Mockingjay Part 1, and it was released as part of the official soundtrack. The song was certified platinum in Canada and double platinum in the United States. Now, though, Collins has decided to reveal the history of "The Hanging Tree."

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According to Collins' new Hunger Games novel President Coriolanus Snow was himself just a teenager. He was assigned to serve as a mentor to Lucy Gray, the District 12 Champion in the Hunger Games, and for his impropriety Snow was sent to District 12 to serve as a Peacekeeper. He didn't mind much, pursuing his relationship with Lucy, and even briefly contemplating abandoning his future in the Capitol. Unfortunately the romance was doomed, in large part because it was conducted in the context of a brewing potential uprising in District 12. At one point Snow and Lucy bore witness to the hanging of one rebel, Arlo; his lover Li attended as well, and was arrested as she witnessed his death. These tragic events inspired Lucy to write the song "The Hanging Tree." She had no idea that, so many years later, the song would become key to the rebellion that overthrew the Capitol - and her own lover, Coriolanus Snow, by then president of Panem.

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Curiously, though, some of the lyrics do not refer to the execution itself; rather, they refer to a midnight tryst between Coriolanus Snow and Lucy Gray herself.

"Are you, are you

Coming to the tree

They strung up a man

They say who murdered three

Strange things did happen here

No stranger would it be

If we met at midnight

In the hanging tree."

Snow came within a hair's breadth of abandoning his career at the Capitol and fleeing into the wilderness, but his ambition and lust for power ultimately proved greater than his love for Lucy. An unguarded comment from Snow led Lucy to realize his true nature, his viciousness and potential for treachery, and she disappeared in a storm. Although Snow attempted to pursue her into the forest, he was misled because Lucy had taught some mockingjays her song "The Hanging Tree." Lucy's fate was never revealed, and "The Hanging Tree" outlived all memory of her - living on to the time of The Hunger Games.

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