This book shows how all necessity – logical, mathematical, physical, transcendental or metaphysical - is consequent. It argues that reason and God, although necessary with respect to essence, are, with respect to existence, eternal contingencies. The first chapter critically reverses Meillasssoux’s claim for the necessity of contingency. The second chapter positively outlines the possibility of contingent necessity by means of Boutroux’s neglected book The Contingency of the Laws of Nature. The third chapter further grounds this possibility by means of the early Schelling’s reading of Plato’s Timaeus. Chapters four and five turn to Schelling’s late philosophy, detailing an ontology that treats reason and God as matters of fact rather than as truths of reason. Chapter six draws parallels and differences between Schelling’s approach and the “passing by” of the last God in Heidegger’s Contributions to Philosophy. The book’s final chapter argues for a new typology for philosophical theology, theomonism, and how this conception can provide a contemporary response to the Euthyphro Dilemma. While some authors, e.g. Meillassoux and Kearney, have recently argued for a possible God who does not exist now but may in the future, this book addresses an unexplored alternative, a contingent God that eternally exists but could have eternally never existed.