This project deals chiefly with the U.S. West and the contradictory intersection of national-democratic and imperial spatialization imperatives during the era of post-Civil War reforms. The project draws on digital history approaches to inquire into the legal and social impact of democratic reforms on colonized Indigenous populations and the accessibility of colonization’s opportunities to formerly enslaved African Americans. The first section of the paper lays out the project’s key terms. It explains what is meant by describing the United States as a nation-state with imperial extensions and what is unique about this combined spatial format. The section shows how this is different from a “nation” or an “empire” or a combination of the two, where the two components remain unaltered. It also discusses how the model enables lines of inquiry that remain underdeveloped in other conceptions. The second section lays out the project’s specific questions and historical contexts. In particular, it looks at how democratic reforms reconfigured the colonization of the U.S. West—and the place of Indigenous peoples and formerly enslaved African Americans in this respatialization. The paper’s third section discusses method—and precisely how an argumentative digital history can produce new insights for the topic at hand and, more generally, within history. After laying out the general style of argument, the section presents concrete examples from the project.