In a 2020 interview
, Plant expanded on the drive that spawned this song.
He'd been out on the rural Southern backroads because he'd been helping the University of Mississippi place historical markers at key Blues history sites. This had him spending long hours alone in his car. As he drove, he listened to AM radio.
"It's quite something to behold," he said of the evangelists he heard on the radio. "It's quite frightening, really."
He'd stop and take notes occasionally as he drove.
Later he had these bits as he sat in the living room of Buddy Miller
, a musician and Grammy-winning producer based in Nashville, Tennessee. Miller toured with Plant a few times and co-produced Plant's ninth solo studio album, Band of Joy
, which came out in 2010. He also co-wrote some of the songs on that album. The later began working together on a sequel to that album.