While many international lawyers are familiar with Francisco de Vitoria (1483–1546), very few have even heard of Paulus Vladimiri (1370–1435) – a Polish priest and jurist who made striking similar arguments to Vitoria on legal universality and the rights of non-Christians a full century before Vitoria. This divergence of consciousness, I argue, provides a unique opportunity to explore questions of canon, reception, and the role of ‘founding fathers’ within international legal thought. Centring Vladimiri as an ‘Eastern European’ figure, I argue that his non-reception is largely the result of how Eastern Europe implicitly functions as a distinctly liminal space within international legal thought that makes any possible ‘founding father’ from this region immensely difficult to imagine. I examine this dynamic through the differing postwar efforts of the Polish jurists Kazimierz Grzybowski and C. H. Alexandrowicz to include Vladimiri within the international legal canon. In examining the background structures of twentieth-century international law, I conclude that, in a manner directly connected to the liminality of Eastern Europe, neither Soviet nor Third World nor Western imaginations could easily receive Vladimiri within their fundamentally political narratives of normative order that shaped their international legal approaches. However, despite this historic non-reception, I argue that Vladimiri, and the question of Eastern Europe more generally, holds great promise in our current global moment. Particularly, engaging Eastern Europe’s liminal character offers a more sociologically grounded alternative to the reductionist Schmittian view of international law as a product of inescapable conflict in a world of exclusionary ‘greater spaces’.