This book is an intellectual biography of one of the most controversial thinkers of nineteenth-century Germany: David Friedrich Strauß (1808–74). It examines Strauß’s intellectual development from his first work—Das Leben Jesu—to his last—Der alte und der neue Glaube. This is the first comprehensive study of all of Strauß’s most important theological and philosophical writings. It investigates in detail works that have been ignored or treated only superficially: the 1840 Die christliche Glaubenslehre, the 1864 Das Leben Jesu für das deutsche Volk, and the1865 Der Christus des Glaubens und der Jesus der Geschichte. It also examines many writings that have hitherto eluded scholarly attention, especially Strauß’s political writings. It also provides an account of Strauß’s early Tübingen lectures. This book is also a partial defense of Strauß as a philosopher. It argues that his biblical criticism did not presuppose the truth of any metaphysics but was only an application of the historical method. His method was essentially limited to an internal critique of the Bible and did not apply alien standards to it. Strauß’s theory of myth, which went through several formulations, was essentially an attempt to explain the social and cultural origin of religious belief. It did not hold that myths are fictions but only the expression of the values of a culture. The idea of a Volksgeist was not a metaphysical postulate but a heuristic maxim to investigate the social, political, and historical factors behind the formation of a religious belief. The book concludes with a chapter defending Strauß against his most eminent critics, Nietzsche, Treitschke, and Schweitzer.