Amber Run is a Nottingham-based band comprising Joe Keogh (vocals), Will Jones (guitar), Tom Sperring (bass), Felix Archer (drums), and Henry Wyeth (keyboards). They were initially just called Amber but changed after finding out there was a German trance singer-songwriter with the same name.
Keogh explained the inspiration for this song to The Sun: "I was getting really angry about this dead cynicism amongst music makers and listeners," he said. "So 'Spark' was in retaliation to that. We wanted to make an infinitely optimistic tune."
Kacey Musgraves originally offered "Follow Your Arrow" to her friend Katy Perry. However, Perry thought Musgraves should record the song herself as it seemed, "like something that you would totally say."