This project details the emergence of racial ideologies immanent to late medieval writings on the bodily sensorium. In fourteenth and fifteenth-century England, poets, theologians, natural scientists, and preachers effectuated the experience of morality proper to the good Christian subject. Moving between investigating the physical sensation of sin in one’s own body and prescribing ways of discerning the morality of others in their physical appearance, these writers transform the scene of perception into a charged site for discerning moral truth. The project documents the formation of a burgeoning racist subjectivity. I argue that the Middle Ages inaugurates modes of visceral empiricism that have a higher claim to truth than commonplace sense perception. The literalization of transubstantiation debates, in hundreds of popular miracle stories where Jews see bread becoming bloody flesh, is a paradigmatic trope of the sensual perception I am describing. Late medieval texts rely on this sensual logic as a means to assign racial hierarchies. “Tender flesh,” a term drawn from the language of the archive, names the concretization of sensory data in depictions of deformity and gore that is attached to perceptive modes of vigilance and protective feeling in Christian subjects. In this regard, I track a central antinomy of the late Middle Ages: the desire to apprehend morality in physical appearance that exists in paradoxical tandem with skepticism over the capacity of sensory data to reveal higher truths. In this contradiction I locate a genealogy of racial interpellation; the incipient history of a subjectivity that relies for its coherence on the misrecognition of racialized others.