Flogging Molly is a seven piece Irish-American Celtic punk group comprising Dave King (lead vocals), Bridget Regan (fiddle, tin whistle, uillean pipes), Dennis Casey (guitar), Matt Hensley (accordion, concertina), Nathen Maxwell (bass guitar) Bob Schmidt (mandolin, banjo) and George Schmidt (drums). King explained to Alternative Press magazine how the band contributed to the writing of this song: "We didn't [originally] have an intro for the song. We were just going to go "one-two-three-four" and [kick into the riff]. Then Nate started playing around with this bass line. He's a big hardcore fan. And sure enough, he played the riff, and that was it.
As a band, it's a really democratic thing. I think Bridget came up with the riff. But she wrote it like a ballad. And I heard it and grabbed a hold of it and sat down with my guitar and came up with the main body of the song. We all sit around and give our opinion for every song."