This song started off as an a cappella ditty that vocalist Hannah Reid came up with in the shower. London Grammar's Dot Major explained to Billboard magazine:
"It was basically like, she used to sing that when we were sound checking in 2015-16. So we took the a cappella and we just arranged the music around it. But because I think the vocal just solo is so powerful that I think we wanted people to hear it like that."
"Rooting" was released as the lead single from Truth Is A Beautiful Thing on January 1, 2017. Leading the record with such a stark a capella tune could be considered a surprising choice. Hannah Reid explained why they chose to preview the album with this track.
"The first song we put out on the first album was 'Hey Now,' which kind of also wasn't that poppy either, and we just wanted the first thing to be kind of special. Rather than maybe something that was going to be really catchy and played on the radio and -- I mean we don't really know what that is, or how to make music to be catchy anyway. Maybe it is, maybe it isn't. But we just love the song and it kind of, the lyrics kind of fit with the timing of the release. 'Let winter break…' and it was winter, and we just kind of thought it fit."
The song was produced by Tim Bran of British reggae-rock band Dreadzone and Little Boots collaborator Roy Kerr. The pair also worked on London Grammar's first album.
"Sloop John B" is a traditional West Indian folk song, and it was a huge hit for The Beach Boys in 1966. They tweaked the lyric, "This is the worst trip since I've been born" to "...I've ever been on" as a wink to acid culture.