This talk aims to make sense of some puzzling patterns in the incarceration rates of Black and White Americans since slavery, particularly why the Black incarceration rate was lower in the South than in the North for much of the 20th century, why it was lowest in the South’s cotton belt, and why it began to increase in the second half of the 20th century. I argue that these patterns partially reflect the long history of the demand for agricultural labor in the South. To evaluate this claim, I examine how two shocks to agricultural labor demand—the boll weevil infestation and the introduction of the mechanical cotton harvester—affected incarceration in the South. The talk will close with some reflections on how these findings clarify the relationship between incarceration and slavery, the criminal surety system, and broader shifts in the agricultural economy in the United States.