Songfacts®:

• This is a track from Sonic Highways, an album containing eight songs, each recorded in a different US city. This cut was recorded in Nashville, Tennessee. Bassist Nate Mendel told NME: "The song 'Congregation' is a play on how a lot of the folks in the Nashville country music scene came together in church, in a sort of gospel environment, to learn their craft."
• The song features guitars and backing vocals from Zac Brown of the Zac Brown Band. Dave Grohl previously collaborated with the country group when he produced and played drums on their 2012 The Grohl Sessions, Vol. 1 EP. The Foo Fighters frontman told Q magazine of their original collaboration: "Zac Brown is an enormous country star. I met him in a store and he asked me to produce an album. I'd never heard of him. I said to someone, Zac Brown has asked me to produce him' - they said, 'You should do it, he's huge' So I did the record without hearing any of his songs."
• The lyric, "And they're singing like a bluebird in the round," references Nashville's iconic Bluebird Café. "The Bluebird I knew a little bit about, but I learned a lot," explained Grohl. "In Nashville, it seems like there are these rites of passage that you have to go through to become a star, whether you're a singer or a songwriter, and the Bluebird is really one of those. If you can get down at the Bluebird, you've got a gig."