Robert Plant - a man with admirably open ears - used to like referring to Zeppelin at their peak as "the world's loudest folk band". He also turned up for a few early punk gigs when many other rocks gods of his generation were terrified of the phenomenon and has been known to join in the odd casual campfire session at world music events like the Tuaregs' Festival in the Desert.
It was certainly the Led Zep version of Gallows Pole that got me interested in that particular song, and led me to discover many older versions of it. Similarly, it was the first two or three Rolling Stones albums which first got me curious about Muddy Waters, Jimmy Reed and Robert Johnson. As Muddy himself once said of the Stones: "They stole my music, but they gave me my name." He thought that was a fair exchange, and who are we to argue?