“Mythical Night: Religion and the Unconscious of History” retrieves the category of myth as a critical term for the study of religion. It does so by turning to the interwar period, a moment of social, political, and intellectual upheaval of such a scale that European thinkers could not explain their situation by means of any proximate cause. Instead, they interpreted their moment of crisis as the eruption of latent historical forces that could only be figured through the language of myth. This case nuances recent conversations in the philosophy of religion that take the convergence of the archaic and the modern as central for thinking about the problem of historicity. Arguing that when historicity is pushed to the limit questions of religion inevitably come to the fore, this dissertation claims that a robust concept of history must account for what is unaccountable in it, characterized here as the “unconscious of history.” The dissertation traces the historical and conceptual vicissitudes of myth within modern philosophy and religious thought. Denigrated since World War II thanks to its association with fascism, myth has recently been rehabilitated by critical discourses seeking emancipation from the most violent aspects of modernity. To historicize shift, Chapter 1 presents a political genealogy of the ways in which Enlightenment and Romantic conceptions of myth were mobilized to negotiate the boundaries between reason and revelation during the long nineteenth century. The next three chapters treat German-language figures who, between the World Wars, paradoxically made recourse to the region of myth to ground their intellectual projects. Chapter 2 brings together the clinical, theoretical, and cultural writings of Sigmund Freud to show how the project of psychoanalysis rests upon the two myths of the drives and the primal murder. This chapter argues that for Freud, the unconscious transmission of a repressed truth ceaselessly generates religion anew. Chapter 3 examines the Jewish philosopher Franz Rosenzweig and his construction of an “everlasting protocosmos” as the precondition for the historical world of revelation. It argues that the historical relationship between paganism, Judaism, and Christianity is figured to critique the tradition of dialectical philosophy. Chapter 4 turns to the philosopher Martin Heidegger, rereading his more political writings from the 1930s in view of recently published archival material. Not only does mythology prove to be a controlling concept in his corpus but its object of investigation is redefined as a stratum of history that never appears as such. The political aims into which these thinkers channel such strata of history range from modestly liberal to reactionary. Chapter 5 then turns to contemporary figures who, drawing on the concepts and sources discussed thus far, put them in service of leftist political projects. The conclusion suggests why the philosophy of religion is especially equipped to reckon with a fundamentally ambiguous mythology figured as resistant to the claims of reason and considers the implications of this for questions of method.