Actually, there were 3 more people who were called "The King of Rock and Roll". They are Fats Domino, Bill Haley, and Alan Freed (the radio promoter, who made rock n' roll famous), but I would also put them out of this poll, because the real kings are exactly the ones that you included.
Although Elvis is the biggest American music icon ever and he is the king up to this day, I voted for Chuck Berry, because I knew that he was going to have less votes than Elvis. "The Whole World Knows the Music. Nobody Knows the Man." For me Berry is the real king, because he is one of the greatest song-writers of all time, and actually he is the father of rock n roll, while Elvis hasn't written one song himself. While, on other hand, Little Richard is more self-called king - he boasts all the time about how he is the real king. That's why I'd put him on 3rd place.
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