The name "Dread Pirate Roberts" is (quite cleverly, IMHO) picked up from the character from The Princess Bride [aside: go watch the film -- it's great fun!].
It is possible that this "person" is much like Satoshi Nakamoto, given that in The Princess Bride, the pirate is not actually one person, but a series of individuals who periodically pass the name and reputation to a chosen successor.