The present book examines how conflicts between nationalities within transnational church networks were negotiated between the World Wars. To that end, it investigates internal church disagreements over the status of German-speaking Catholic minorities in two different border regions, East Upper Silesia (Poland) and Alsace-Lorraine (France), exploring the interactions between these peripheral church regions and the center in Rome.

In both of these regions, the Catholic Church was a factor to be reckoned with. Its regional and local influence was undergirded by its own highly developed press sector, influential Catholic regional parties, and Catholic associations – organizations, in other words, that in many cases traced their roots to the time of Bismarck’s Kaiserreich. Catholic priests typically enjoyed a high level of respect within the populace. Yet, the clergy rarely presented a unified front, at least not in the conflicts of the 1920s. Controversies over the use of the German language in religious instruction or in Sunday sermons divided Church elites no less than the population at large.

Especially during the first decade after Versailles, German-speaking Catholic populations in border areas used their influence to advocate for greater autonomy for their regions. In the process, the organization of political interests was advanced through the efforts of various actors. In East Upper Silesia, it was mostly lay functionaries from the Association of German Catholics who were especially active politically, thereby opposing the official leadership of the Diocese in Katowice. In Alsace-Lorraine, a similar role was played by members of the priesthood. In both cases, activists could count on financial, diplomatic, and ideological support from the German Reich. During the 1930s, in both East Upper Silesia and Alsace-Lorraine, internal tensions within the Church receded into the background, although they never disappeared completely. The struggle against external opponents – National Socialist groups as well as state interference in church affairs in East Upper Silesia, leftist national governments in Alsace-Lorraine – helped create at least the impression of a unified Church front.

These conflicts on the peripheries of the Catholic Church cannot be truly understood without also considering the influence of decisions made at the center, in Rome. On the one hand, the Vatican made important decisions, for example in appointing bishops or negotiating agreements with national governments. On the other hand, both priests and laypeople enjoyed a distinct advantage when it came to being informed about regional affairs, and they were capable of utilizing this advantage in order to influence decisions made in Rome. The various opposing parties interpreted and sometimes intentionally ‘misunderstood’ encyclicals and other papal communiqués, and not infrequently used them to justify their own positions.

The Catholic Church was able to defuse nationalities conflicts in border regions only to a very limited extent. To be sure, the Church committed both the clergy and (to a lesser extent) laypeople to an approach that prioritized religious principles over political positions. In some respects, that helped dilute extreme nationalist positions. Within the ethnic German populations of the two regions, taking on either Polish or French citizenship, respectively, was more or less uncontroversial, largely owing to the Vatican’s postulates in regard to the theory of the state.

In other respects, however, the Catholic Church’s actions aggravated such conflicts. It had taken a long time for even a vague awareness about the attributes of modern nationalism to develop within the Vatican and its immediate sphere, an awareness that basically manifested itself in a moralistic distinction between a ‘good’ moderate, Christian-influenced national feeling and a ‘bad’ excessive (pagan) nationalism. Rome viewed its dealings in regard to controversial issues that impinged on questions of language and culture in the border regions in quite different contexts: against a backdrop of religious considerations or as part of its diplomatic relations with individual states. The result was that the Holy See supported minorities in some respects, such as in most conflicts over language, while backing the position of the nation states in others, for example the boundaries of dioceses or the appointment of bishops. Both clergy and laypeople in the border regions frequently interpreted guidelines from the Vatican in their own favor and then attempted to pass them off as generally applicable political statements, which had the effect of intensifying internal church conflicts in the border regions.