More has been written about the Civil War than practically any other era in American history. In part, this was because more of the participants in the war were literate and could record their experiences. Since the war was waged across a continent and involved millions of soldiers and even more civilians, it also generated records on a scale never seen before. The war’s official documentation, collected in The War of the Rebellion: Official Records of the Civil War, assembled by the federal government, runs to 128 volumes. And that does not include collections of letters, diaries, photographs, and other records collected by individuals and organizations in the years since the war’s end. These records sought to uncover the root of the war. And, out of all these records, a single factor emerges as the most compelling cause: the system of enslavement of Black Americans.