When trying to interpret this song, keep in mind that Dylan was experimenting with LSD around the time he recorded it.
This is the last track on the album. It is eleven minutes long, and was Dylan's longest song up to that point. Dylan rarely plays it at concerts, but when he does, it can stretch out to 45 minutes.
The song is about three men who were in town with the circus and were accused of raping a girl in Duluth, Minnesota. On June 15, 1920, a mob broke them out of jail and lynched them. Postcards with pictures of the hanging were sold as souvenirs. Dylan's father, Abraham Zimmerman, was 8 years old and living in Duluth at the time of the hangings.