Robert Johnson was an American blues musician and songwriter whose most influential music came out in 1936 and 1937, and he has influenced many musicians in later years (like Led Zeppelin and Eric Clapton). He is now considered to be a master of the blues (most particularly of the Delta blues).
For most of his time as a performer, he was a travelling performer who played on streetcorners, juke joints, and at Saturday night parties. But during this time, he received very little recognition for his talent or style. He had only two recordings (one recorded in San Antonio in 1936 and one in Dallas in 1937), and he only recorded 29 songs (and there are also only two known photos of him). These recordings were later made famous when they were played a Carnegie Hall; a presentation was put together to expose audiences to the music that influenced jazz and swing. Unfortunately, Johnson had died six months before this concert was put together, and it was only his recordings that were presented to the audiences.
There is a legend surrounding his music and how well he played. In the beginning, when he first began playing music, he was not considered to be anything too special, but he went away for a year, and when he came back, he had become much better. He was suddenly so much better that a legend started forming that he had gone to the crossroads and sold his soul to the devil to gain his skill.
In truth what happened was that he had gone to another blues musician and began taking lessons from him. They would go into a graveyard in the middle of the night to practice, which may have added to the story about selling his soul to the devil.
Johnson may have made more recordings, but he became one of the founding members of the 27 Club instead, when he was killed by the husband of the woman he was seeing. He was taunting the fact that he was seeing a married woman, and her husband poisoned a bottle of whisky that Johnson was given. And it was not until the 1960s that he really gained popularity.
Teenagers from the ‘60s would go to record stores and buy boxes of records, not knowing what it was they were getting. Those two records that he recorded were often inside those boxes, and the kids were exposed to his music. Those kids were so influenced by what they heard that they changed music going forward, changed it because of the things that they had heard.
Despite the fact that he did not actually sell his soul to the devil, the story that he did may have only added to his popularity and made his life more interesting (adding to the mystique).