There are many excellent studies of the life and thought of Reinhold Niebuhr (1892-1971), prominent Christian ethicist, social philosopher, and political activist of the American Century. Most studies focus on his mature works of mid-century, particularly his theological ethics. The following study treats his emergent theory of history between 1927-1934, especially the idea of progress and the narrative of modern capitalist society. During this formative period Niebuhr wrote three major books (Does Civilization Need Religion? [1927], Moral Man and Immoral Society [1932], and Reflections on the End of an Era [1934]) which reflect his intellectual passage from religious liberalism and the politics of persuasion to "Christian-Marxism" and the politics of power. The following thesis will trace the diverse historiographical influences found in these works, from the church-historical perspective of Ernst Troeltsch to the dialectical materialism of Karl Marx. It is common to say that Niebuhr was purely a theologian of history. But following Ricoeur and White, I describe the main ingredients of a philosophy of history that are present in these writings: myth, plot, social processes, patterns of progress and cycle. Moreover, he was a "thinker in time"--these philosophical elements combined to render a plausible and meaningful narrative context for social action. In the early period Niebuhr began his lifelong critique of Enlightenment, capitalism, and the idea of progress. Following Robert Nisbet's analysis of the concept of progress in Western cultural history, I will argue that Niebuhr traverses his own peculiar dialectics of history, moving from the idea of progress-as-freedom (in the twenties) to the idea of progress-as-power (in the thirties); from the form of irony to the form of tragedy; from the concept of the voluntary reform of the excesses of captialism to the concept of the frank use of coercion to implement a socialist alternative to captialism. His philosophy of history in this period thus reflects in Christian idiom aspects of the very antinomies of the Enlightenment regarding personality and power, freedom and fate, which he desires to overcome.