We often hire a wonderful band called Spare Parts to do music for balls. They are a fantastic historical dance band. One song they play is called "The Jenny Lind Polka." It is a great song, but I had never given it more thought than that.
But apparently Jenny Lind was a famous singer, referred to as the Swedish Nightingale. Interesting. I stumbled across this picture of her in a pretty dress. I also found this very weird story about an antique "scarecrow" that ended up being a statue of Jenny Lind, apparently from the bow of a ship. If you're curious, it's here.