The antebellum era saw an epochal shift in politics: nature transformed into a key site of the political. No longer seen as a refuge from human concerns, biological existence itself became a key new resource for conceptualizing human difference and an administrative target of political power. This essay reveals sentimental literature to march in step with this shift. This mode overwhelmingly associated with the domestic realm and even the trite and saccharine nonetheless reveals an emergent biopolitics attuned to disciplining the individual’s nature and conceiving of humanity as a population whose biological quality could be optimized. An ideology that sutured literature and science together in an era in which divisions between them were just beginning to form, sentimentalism helped move politics into the flesh.