Upper Silesia with its mixed Polish and German population was a province of Prussia and a part of the German Reich prior to World War I. In the Treaty of Versailles, after the defeat of Imperial Germany and Austria-Hungary in World War I, it was decided that the population of Upper Silesia should hold a plebiscite to determine the division of the province between Poland and Germany, with the exception of a 333 sqkm area around Hlučín (Hultschiner Ländchen), which was granted to Czechoslovakia in 1920 despite its German-speaking majority.