Robert Johnson, a black American blues guitarist and singer from the early twentieth century, is considered one of the most influential figures in the development of American popular music. The rock and blues star Eric Clapton called him "the most important blues singer that ever lived," and to Rolling Stones guitarist Keith Richards, Johnson's songs are the finest in all of the blues. Yet the most interesting thing about Robert Johnson is how much of his fame is based on things we don't know for sure.

Johnson was born in Mississippi in 1911-or maybe it was 1912. He played several musical instruments in his childhood, but could not play the guitar well. When he was about 18 he went away to practice the guitar with a blues musician named Ike Zinnerman, who was rumored to have learned the instrument by playing in graveyards at midnight. When Johnson returned a short time later, he amazed everyone with his improved technique. This inspired the legend that he had sold his soul to the Devil in order to become a great blues musician.

During the Great Depression of the 1930s, Johnson traveled around the American South, usually playing popular songs rather than his own compositions, which were darker and more disturbing. He used different names in different places and never stayed anywhere for long. Then, in 1936 and 1937, he finally recorded the songs that people today remember him by-songs that have supported the legend of his deal with the Devil. With their mysterious high singing and mournful guitar, songs like "Cross Road Blues" (made famous by Clapton as "Crossroads," which he performed with the band Cream), "Me and the Devil Blues," and "Hellhound on My Trail" sound strange and exciting even today.

Johnson died in Mississippi in 1938, when he was still in his twenties. There was a rumor that someone gave him a poisoned drink. But there is as much agreement about this as there is about the location of his grave: in Mississippi there are three different spots where people think he is buried.

It may seem foolish to believe that Johnson sold his soul to the Devil. When we look more closely at his story, there are simple explanations for some of its mysteries. Ike Zinnerman, for example, liked to play the guitar in graveyards because they were quiet places where no one would bother him. Johnson lived at a time when most black music was connected to the church, and religious black people thought that playing non-religious music was "evil." It is also worth remembering that the story of a man who makes a deal with the Devil for special power is an old one in the West, going back to the sixteenth-century German legend of Faust. In nineteenth-century Italy, the violin player Niccolo Paganini was also thought to have received his famous musical ability from the Devil. But Paganini died years before the invention of recording technology, so his skills are as much a part of legend as their source. This is the paradox of Robert Johnson: for all the mystery surrounding his life, his amazing recordings are preserved for anyone to hear.

But it may be foolish to look for truth even there. Music experts now say that when Johnson's songs were put on LP records, someone changed their speed, and made them 20% faster. No one knows whether this was an accident or on purpose, and the original recordings are now gone. So the high, mysterious voice of Robert Johnson is as uncertain as everything else about him.

Perhaps the one truth of Johnson's story is about humanity, not about him. When we are faced with a man whose talent seems magical, it is easy for us to suspect that he must have paid a secret, terrible price for it. It is not so easy to believe that something could simply be a gift.

• 11. Thanks to Eric Clapton and Keith Richards, Robert Johnson's life is now well understood.
• 12. Johnson's talent for playing the guitar appeared very suddenly.
• 13. American audiences became familiar with Johnson's original songs during his travels around the South in the Great Depression.
• 14. It is generally agreed that Johnson died from poisoning.
• 15. Ike Zinnerman's personal habits contributed to Johnson's mysterious reputation.
• 16. There are cultural reasons that explain people's belief in Johnson's deal with the Devil.
• 17. Because Johnson's legend was so well known, people also began to believe that Niccolo Paganini had made a deal with the Devil.
• 18. Johnson's ability on the guitar is easier for people today to judge than Paganini's technique on the violin.
• 19. Johnson's recordings were made slower when they were put on LP records, so they do not sound exactly the way they did when he played them.
• 20. Johnson's legend shows our tendency to believe that people with bad luck have done something evil to deserve it.