“A Freedom No Greater Than Bondage: Black Refugees and Unfree Labor at the Dawn of Mass Incarceration” centers the lives of Black refugees and formerly enslaved people whom the Union army incarcerated during and after the Civil War. This research tackles central questions: Why and how did the Union military justice system, which expanded to police white citizens’ politics, come to be used against the enslaved and recently emancipated? How did the U.S. state expand its carceral capacities in this period? While there have been many studies that center enslaved persons’ transition “from slavery to freedom” and the role of the Union army, I argue that the Union military justice system created a blueprint for a penal and carceral system that was later coopted by Democrat-controlled governments in the South. My work fills a critical gap in the scholarship by locating the dawn of mass incarceration in the Civil War rather than the Jim Crow era. I thus demonstrate how policing and state violence underpin what many think of as institutions and locations of progressive reform, bringing to light the process by which the enslaved became “slaves of the state.” Their narratives complicate popular understandings of emancipation, which elides continuing forms of slavery and fundamental role of anti-Blackness in nation-building. This study uses the trial records, testimonies, and letters of those who did not make it to freedom in 1865 and those who never made it all. I therefore use military records to trace the making of U.S. incarceration but also to foreground Black resistance against it.