Kacey Musgraves' “Rainbow" is more like an encouraging letter than it is a song. The piano ballad that closes out the glowing Golden Hour album is one that's taken on many identities since it was written, six years before its release.

"Rainbow" originally began as an encouraging note the singer was inspired to write for herself after reading her horoscope. It later served as the final song Musgraves’ grandmother heard her write—one she loved so dearly, it was performed at her funeral. Now it’s transformed into a message of hope for anyone in the midst of dark times, one that fittingly completes the singer's multi-faceted latest album.

"For a long time, that was a really hard one to hear, but I thought that it fit really nicely on the record," Musgraves says. "It turned into a song as a little message to myself, and then ended up being a song for anybody with any kind of weight on their shoulders."

The song is met with another personal touch in the fact that it's presented as a raw recording on Golden Hour. While Musgraves is conscientious in perfecting each song to the best of its ability, she opted for a more vulnerable approach on this one, letting the piano, lyrics and her emotion drive the song.

"Every night in the studio, we would end the session with turning all the lights off and just sitting by the piano and recording a live version of 'Rainbow,'" she explains of the process, selecting the best rendition at the end to include on the album. "It's very vulnerable as a singer to commit to showing a live track because there's no fixing it. Everyone sees what your capabilities are right then and there.”

Though the song started as a personal note of reassurance, Musgraves hopes it will serve as an anthem for those facing adversity, particularly in the LGBTQ community. "I feel a kinship and a friendship with that community. They really opened my eyes up to a lot of different things that I wasn't aware of growing up in a small town in Texas. I will always be an ally and a strong supporter," Musgraves vows.

"'Rainbow' is something that I can dedicate to that community, but also to anyone who has any kind of a weight on their shoulders. It was written as a message to my own self, but anyone who is feeling like they need that is welcome to run with it," she says.

Musgraves weaves many messages of hope and introspectiveness into Golden Hour, which debuted at No. 1 on the Billboard Top Country Albums chart following its release in March of 2018, in addition to reaching the top 5 on the Billboard 200. On Feb. 10, Golden Hour won the Album of the Year award — an all-genre award — at the 2019 Grammys.

*This story was originally published in May 2018. 

Watch: Kacey Musgraves Performs "Rainbow" at the 2019 Grammys: 

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