Songfacts®:

• Florence Welch wrote this choral song after becoming fascinated with a historical phenomenon called choreomania, in which crowds of people danced themselves to exhaustion. First recorded in Aachen (present-day Germany) on June 24, 1374, outbreaks of dancing mania continued periodically in mainland Europe until the 17th century. During such episodes, groups of up to thousands of people would dance uncontrollably, screaming, shouting, and claiming to have visions until they collapsed from fatigue.
• A poet friend of Welch, Juliano Zaffino, told her about choreomania. He wrote a poem, "Strasbourg," about dancing mania, which namechecks Welch. Zaffono's poem took inspiration from an outbreak that killed hundreds of people in Strasbourg, France, in 1518.
  
  It began when a woman danced in the streets of Strasbourg for about five days. Eventually, 400 women danced themselves to death. "What I found so fascinating about it is they have so many theories as to why it happened," said Welch to NPR. "One of them, which I found really interesting, was that it could have been psychological because of stress, because of all the other plagues that were happening, because of how hard life was in the Middle Ages. It was like a psychological phenomenon, and I just really related to it."
• Welch recorded "Choreomania" for Dance Fever, titling the record after the track. She began work on the album in New York with Taylor Swift's producer Jack Antonoff, not knowing if they'd hit it off. "I never start working with anyone at this stage in my career, unless we get in the studio and do something, and that really tells you whether something's going to work," Welch told Apple Music. "You're never like, 'Yeah, let's do this,' until you've had a play date, and on this play date we wrote 'King' and then 'Choreomania.' I'd had 'Choreomania' and it was in a very demo-like state, and what Jack did to it, he took it so far. I was like, 'This guy's really good. He's really, really good.'"
• Welch also worked with American producer Thomas "Doveman" Bartlett on the track. They previously collaborated on the fourth Florence and the Machine album, High as Hope, and on the 2019 single "Jenny of Oldstones."
• Dance Fever became Florence + the Machine's fourth record to top the UK albums chart, following 2019's Lungs, 2011's Ceremonials and 2015's How Big, How Blue, How Beautiful.
• Want another song about the historical phenomenon of dancing mania? Check out Julia Holter's "Underneath the Moon."