Roy Harper is a folk musician from England whom Jimmy Page met at the Bath Festival in 1970. He became close friends with members of the band, who invited him to perform as the opening act on some later Led Zeppelin concert tours. In 1971, Page played on Harper's album Stormcock, appearing in the credits under the pseudonym "S. Flavius Mercurius". Harper was also approached to sign up with Led Zeppelin's newly created Swan Song Records but was already contracted to EMI's Harvest Records label. In 1985, Page recorded an album with Harper called Whatever Happened to Jugula? Harper explained:
I used to go up to [Led Zeppelin's] office in Oxford Street, where Peter Grant and Mickie Most would be. And one day Jimmy was up there and gave me the new record. I just said thanks and put it under my arm. Jimmy said "Look at it". So I twirled the little wheel around and put it back under my arm. Very nice and all that. So he went "Look at it!" Then I discovered "Hats Off To (Roy) Harper." I was very touched.[6]
According to Page, during recording sessions for Led Zeppelin III, the band "did a whole set of country blues and traditional blues numbers that Robert [Plant] suggested. But ["Hats Off to (Roy) Harper"] was the only one we put on the record."[7]