This dissertation examines the Catholic clergy of a German diocese (Mainz) during the middle of the nineteenth century, a period that witnessed the transition from religious liberalism to neo-orthodoxy (ultramontanism) as the Catholic clergy’s predominant tendency. Despite extensive research on nineteenth century German ultramontanism at the level of both church and political elites on the one hand and of lay piety on the other, little work has yet been done on the crucial middle factor: the clergy themselves. Using neglected archival sources, especially documents written by the parish clergy themselves, it explores the mental and cultural world of Catholic priests as they underwent this transition from liberal to ultramontane Catholicism. It also traces the struggle within the clergy between liberal and ultramontane factions, and the fate of both under the ultramontanizing episcopacy of Wilhelm von Ketteler after 1850.

Among the study’s chief findings is that matters of personal honor loomed surprisingly large in clergy concerns, often trumping the sacral and religious elements in their self-image. The demands of this culture of honor—closer to those of bourgeois respectability than to those of official Tridentine priestliness—in turn affected clergy reception of the regime of increasing professionalization and oversight that characterized both liberal and ultramontane episcopacies during the century. For the Ketteler episcopacy especially, the culture of priestly honor offered both hurdles and points of egress to the ultramontanization program.

This study also found that liberal Catholicism was actually in the ascendant among the Mainz clergy at mid-century, and that it was only elite pressures—chiefly episcopal and papal—that reversed this trend and assured the rise of neo-orthodoxy. Other factors, such as the “democratization” and “ruralization” of clergy recruitment, played no evident role. Nor did pressure from the laity below drive the process. Overall, the Mainz clergy served as a transmitter—from above to below—of ultramontane religiosity.