From Silesia to Luxembourg: Interwar Arbitral Tribunals and the Emergence of Supranational Adjudication in Europe

Forschungsprojekt

For a long time, the origins of the legal forms of European Integration have been obscured by its ‘sui generis’ narrative – a story of novelty and exceptionality that sought to demonstrate a clear break from the failures of earlier international law. This narrative has come under scrutiny over the last years. ‘Supranational’ adjudication, as a key innovation of the nascent European Court of Justice (ECJ), does not emerge after 1945; it builds upon a complex constellation of interwar experiences with both explicitly supranational discourse and comparable judicial practices.

Recent research has rediscovered the innovative dynamics of international law around the League of Nations. Next to (semi-)colonial legal practices explored in related projects, the Mixed Arbitral Tribunals (MAT), established under the Paris Peace Treaties, developed a quantitatively and qualitatively novel body of jurisprudence under international law – notably establishing the international protection of individual rights against states.

A particularly innovative example is the Arbitral Tribunal for Upper Silesia (ATUS). Negotiated within a contentious German-Polish context under the supervision of the League of Nations, it was part of a comprehensive international legal arrangement, securing economic unity against political partition, forming an early example of regional integration. The project approaches the supranational character and lasting influence of these innovative institutions by researching their establishment, operation, and personal and conceptual legacy through a focus on the role of German lawyers and diplomats.

Situated between the history of international law and the legal history of European integration, the project aims to bridge these fields by identifying continuities between interwar legal experiments and the judicial dimension of early European Integration. The project aims to fill three major research gaps by reconstructing the supranational character of the MATs, and particularly the ATUS in the interwar period; looking at their influence on the emergence of supranational adjudication in early post-war European Integration; and examining the role of German jurists as agents of operation, transmission and continuity of supranational law.

Methodologically, the project combines historical-contextual reconstruction of interwar judicial institutions with a legal-conceptual analysis of their supranational characteristics. These dimensions are connected through a focus on German legal actors and their influence on the judicial development of post-war European integration.