It's not every day that a Danish ex-ballerina puts her ethereal voice to the swaying harmonies of a Seattle rock band, but in this week's Mashup Monday Oh Land does just that with Fleet Foxes' "White Winter Hymnal."

About a year ago, dream pop chanteuse Oh Land (born Nanna Øland Fabricius) says she was "in the middle of making my record... Recording and writing myself, it's hard to let other people's music into my head. But ["Hymnal"] cut its way through."

Photos: Oh Land's Mashup Behind-The-Scenes

"I think what was really interesting to me was all of the vocal harmonies and how they sang together," Oh Land says of why she chose to cover the song, which appears on Fleet Foxes' 2008 self-titled album. She calls her arrangement, which prominently features bells, a "picnic setup, which is more like a smaller version of my live set."

But coming in to record a mashup isn't the only thing she's been up to -- and not the only Billboard related thing either. Her album comes out tomorrow (March 15) on Epic Records, and she'll be down in Austin, Texas playing an official SXSW set at Billboard's venue, Buffalo Billiards, on March 17. There's no wonder why we called her an "artist to watch" earlier this year.

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