In many ways, the development of twentieth-century literary criticism and theory can be seen as a prolonged struggle against the pervading influence of nineteenth-century positivist historicism. Anglo-American New Criticism and later French Post-structuralism and Deconstruction are the best-known instances of this conflict. Less widely known, but no less important to contemporary literary studies, are Charles Peguy's earlier debates with French academic historicism in the years leading up to World War One. First examined by Antoine Compagnon in his ground-breaking work La Troisieme Republique des lettres in 1983, it is a period in French literary and cultural history that remains, some thirty years later, largely untreated in English. This book thus addresses an important, albeit relatively unexplored, moment in the development of twentieth-century literary history and theory. By way of Peguy's foundational polemics with modernity and his role in the related 'crisis of historicism', we gain a better understanding of the critical basis from which similar anti-positivist and anti-historicist critiques were later enacted on both sides of the Atlantic. In situating Peguy's passions and polemics within the larger cultural and historical context, Glenn H. Roe invites us to reconsider and re-evaluate Peguy's place among twentieth-century literary figures. Beyond its literary-critical aspects, The Passion of Charles Peguy provides a general view of early twentieth-century debates related to the role of literary studies in modern society, the reform of the French educational system, and the formation of literary history as an academic discipline in both France and abroad.