High Quality Content by WIKIPEDIA articles! The Upper Silesia plebiscite was a border referendum mandated by the Versailles Treaty and carried out in March 1921 to determine a section of the border between Weimar Germany and Poland. The region was ethnically mixed, chiefly among Germans, Poles and Silesians. According to prewar statistics, ethnic Poles formed 60 percent of the population. The period of the plebiscite campaign and interallied occupation was marked by violence. There were two Polish uprisings, and German volunteer paramilitary units came to the region as well. But the area was policed by French, British, and Italian troops, and overseen by an Interallied Commission, and the vote came off peacefully. The Allies decided to partition the region, but before they could divide it, local partisans of Poland and forces from Poland launched an uprising and took control of over half the area. The Germans responded with volunteer paramilitary units from all over Germany, which...