Songfacts®:

• This ethereal, melancholy song has an air of mystery to it. The title doesn't show up in the lyric, and there's even some debate of what the title really is.
  
  Officially it's called "Rosyln," a very awkward spelling that left many wondering if it was an uncorrected typo. But Justin Vernon, the leader of Bon Iver is on record calling the song "Roslyn, Washington," where the TV series Northern Exposure was filmed. Vernon is a big fan of the series, which is where the Bon Iver name comes from. In a 1993 episode where it snows for the first time of the season, people in the Alaska town where the series is set take to the streets and yell "Bon Hiver!" to each other, a French greeting that means "good winter."
• Bon Iver (Justin Vernon) collaborated with St. Vincent (Annie Clark) on this track. They met in June 2009 when they were both playing the Bonnaroo festival. They realized they were fans of each other, and talked about working together. Not long after, Vernon sent Clark a demo of "Rosyln" and she completed the song with him. "It was beautiful, as you can imagine," she told Pitchfork.
  
  St. Vincent is credited as a featured artist on the song, but Justin Vernon is the only writer listed.
• The song ended up on the soundtrack to the 2009 movie The Twilight Saga: New Moon, and was used in the film. That franchise was huge, so the album sold over a million copies in America and went to #1. The song is only on the soundtrack, not on a Bon Iver or St. Vincent album.
• The song was released in 2009 at a time when Bon Iver and St. Vincent were both gaining traction as an emerging indie artists. They both leveled up in 2011, St. Vincent with her acclaimed Strange Mercy album, and Bon Iver with their self-titled album that earned them the Grammy for Best New Artist.
• St. Vincent told MTV News about this collaboration with Justin Vernon, and why it fits right in to the Twilight universe: "He sings in his beautiful falsetto and I'm actually singing very, very low. I think there's something vampirey and creepy about the two of us singing together. It's a simple, stripped-down kind of song. It's really elegant and beautiful."
• Clark and Vernon had been talking about collaborating together for a while, and when Vernon wrote this song neither of them had any idea that this tune would end up on the soundtrack of New Moon. She explained: "We recorded the song for the joy of it, and then it looked like Twilight people were interested in using the song for the movie. So it pretty naturally happened."