After a century of Rationalist scepticism and political upheaval, the nineteenth century awakened to a fierce battle between the forces of secularization and the crusaders of a Christian revival. From this battlefield arose an art movement that would become the torchbearer of a new religious art: Nazarenism. From its inception in the Lukasbund of 1809, this art was controversial. It nonetheless succeeded in becoming a lingua franca in religious circles throughout Europe, America, and the world at large. This is the first major study of the evolution, structure, and conceptual complexity of this archetypically nineteenth-century language of belief and provides a rich account of the theory and practice of religious representation in nineteenth-century art.