The Upper Silesia plebiscite was a plebiscite mandated by the Versailles Treaty and carried out on 20 March 1921 to determine ownership of the province of Upper Silesia between Weimar Germany and the Second Polish Republic.<br />The region was ethnically mixed with both Germans and Poles. According to prewar statistics, ethnic Poles formed 60 percent of the population.<br /><br />Under the previous rule by the German Empire, Poles claimed they had faced discrimination and had been effectively second-class citizens.<br />The period of the plebiscite campaign and the Allied occupation was marked by violence. <br />Three Polish uprisings occurred, and German volunteer paramilitary units came to the region.
