On Sympathetic Grounds offers a new interpretation of sentimentalism, formulating a moving and non-linear cartography of sympathy's vital place in shaping early American thought. During the sweeping transformations of territory, land stewardship, personhood, and citizenship in nineteenth-century North America, sentimentalists evoked sympathy to express a desire for a place both territorial and emotional-what Naomi Greyser coins an "affective geography." Greyser shows how Nineteenth-century Americans' sense that bodies could merge and mutually occupy the same space serves to complicate normative assumptions of intimacy and distance. Consequently, she reveals how this "affective geography" compels our reconsideration of geopolitics and geophysics, of corporeality and ontology. Mapping feelings in and also about space, On Sympathetic Grounds attends to the experiences and perspectives of those whose bodies, labor, space and sovereignty have been occupied to ground others' lives and world-making projects. By intermixing literary and rhetorical studies with critical race and gender theory, cultural geography, American studies, affect studies and the new materialism, this book details how sentimentalism formalized sympathy as a political emotion. The idea of sympathy as driving emotion proved useful to settler colonialism and the maintenance of racialized labor, while also serving as a means of resistance to the resulting geographical displacement and metaphysical dispossession. Philosophers and rhetoricians regard grounds as necessary conditions for argumentation; Greyser treats grounds as geopolitical, geoaffective, and geophysical, mapping them as alternately shaky, unsettling and stabilizing. Circulating across bodies and surfaces, sympathy has enriched conditions for living at the same time that it has mercilessly enlisted some bodies and lives as the grounds for others' wellbeing. Ultimately, On Sympathetic Grounds uncovers a capacious, non-linear cartography of sympathy's vital place in shaping North America.