During and after World War I, Upper Silesia suffered the most fundamental breakdown it had yet seen. Wartime Germany’s newly aggressive nationalism drove a handful of Upper Silesians to the Polish cause, but the vast majority served loyally in the Prussian army. Only German defeat and new Polish statehood in 1918 made it plausible to turn the Oppeln area into a Polish homeland. The Allies’ initial decision to cede nearly all of Upper Silesia to Poland in 1919 was reversed, amid German protest, in favor of a regional plebiscite. While the vote was intended to clarify national allegiances, the bloody campaign fight and chaotic French-led occupation under the League of Nations actually caused a retreat from national loyalties. A near-complete breakdown of communal order disillusioned Upper Silesians with nationalist politics. As plebiscite propaganda shows, Upper Silesians were expected to vote based on material security or cultural benefits, rather than a sense of national duty or belonging. Instead of democratically dividing populations into loyal Germans and Poles, the plebiscite increasingly convinced Upper Silesians of the need to avoid overt national commitment.