This article analyzes the role that categories of racial transgression—specifically, the reviled “white trash” of the rural South—play in the historical construction of racial innocence in America. Writing in 1963, James Baldwin diagnosed innocence as the alchemy by which white Americans turn otherwise visible racial inequality into stories of redemption, virtue, and progress. In this article, I use shifting historical constructions of white trash from the Progressive Era to the post–World War II era to unearth the relationship between transgression and innocence. Beginning in the 1940s, white trash underwent a significant transformation that smoothed the reentrenchment of racial innocence during the era of Cold War liberalism and civil rights. Once figures of suspect racial “purity,” white trash in the postwar period operated as a repository of intractable antiblack violence, mobism, and retrogression. Their movement from racial contaminant to guilty white, I argue, brings into sharp relief the class-inflected transformation of racial innocence during the critical civil rights years: the New South’s commitment to “color-blind” law-and-order and economic progress were together formative of the protection of emergent white middle-class interests in the postwar South and a new kind of racial innocence that has since settled into contemporary national discourses on race.