Set in 1937 rural Mississippi, "Oh Brother, Where Art Thou?" portrays racial relations as being largely based on ignorance and distrust, if not active hatred. Segregation of the races was the unquestioned and unchallenged law of the land.
When black guitarist Tommy Johnson meets Ulysses, Pete, and Delmar, he answers their questions about why he was where they found him by explaining he had struck a deal with the devil, giving up his soul in return for the ability to play the guitar. Pete asks what the devil looks like and Tommy replies, "He's white, as white as you folks, with empty eyes and a big hollow voice. He likes to travel around with a mean old hound. That's right." This description particularly fit Sheriff Cooley, but aptly portrayed the opinion of most blacks about most whites.
The presence of the Ku Klux Klan indicated the feeling of many whites about the blacks in their midst. Their goal was to eliminate the black presence by whatever means was necessary.