A whole bunch of folks in the country music and bluegrass singin' business contributed to the amazing batch of songs that made this weird little Cohen Brothers movie memorable. This was the rock n' roll music of the depression era South and it feels very familiar to me. This is the stuff my kinfolk used to sing on the back porch in the cool of a summer evening.
Here's the clip from the movie where they sing "He's in the Jailhouse Now.":