This dissertation describes how theologically conservative Protestant church traditions in the twentieth-century north and midwest, primarily but not exclusively in the Chicagoland area, established distinct and powerful white supremacist social orders and articulated popular white racial norms that came to transform outmoded southern evangelical white supremacy and to realign the economic, geographical and political entanglements of national postwar “white evangelicalism,” as the tradition came to be described after its transformation. In particular, this work assesses the structural ideology and structural formation of northern and midwestern conservative Protestant churches—their ecclesiology, or doctrines of church order, and their ecclesiasticism, or their institutional orders—as they were articulated in the discursive and material development of related “free church,” fundamentalist and, ultimately, evangelical movements of that century. Moreover, this work connects and correlates white evangelicalism’s racial orders and racial ideologies with the structural ideologies (ecclesiology) and institutional formations (ecclesiastical orders) it promoted as a pro-capitalist religious movement, where possible identifying how those ideologies and formations themselves cause racial order and sustain racial ideology. Ultimately, this dissertation concludes that white evangelicals transformed institutional and ideological white supremacy in the United States by obscuring their own social, political and cultural interests as well as by eliding the human social and material forces behind their movement. By lending all credit for their corporate organization to God, by defining their tradition as a spiritual rather than material or social organization and by limiting their social ethics to prioritize both evangelism and individual regeneration on behalf of the spiritual church, white evangelicals secured their white identity, the white supremacist social orders of their church and the anti-structural individualism of their culture. The dissertation analyzes its themes and constructs its arguments in reference to (1) a history of Scandinavian-American “free church” communities from the late-nineteenth century through the 1950s who came to participate in (2) larger and better-known fundamentalist and evangelical movements that articulated a distinct form of white conservative religious activism and worked tirelessly to consolidate evangelicalism’s social power and establish a new new kind of ‘church’ in the United States (3) by specific economic development programs in America’s white postwar suburbs. Finally, (4) this work describes white evangelicals’ ecclesiastical “sanction” for the economic power structures of newly organized white American communities that helped to justify anew their support for the racial status quo in the United State: white supremacy. In short, the dissertation argues that white evangelicals’ debates over the civil rights movement and racial inequality display how both southern and suburbanized white evangelicals’ modulated their white supremacy through evolving ecclesiological and geographical terms, setting the stage for the so-called “conservative interregnum” of the 1970s and beyond.