The rise of nationalism in Central Europe in the nineteenth century had dire consequences for Silesia, the far-flung, multi-ethnic frontier region of Prussia/Germany, bordering on Austria-Hungary and Russia. The dividing up in 1921 of Upper Silesia between Germany and the newly established Polish nation-state, and the ensuing ennationalization of both regions, triggered off population movements of 300,000 persons before 1939, when Berlin seized the whole of Upper Silesia and embarked on a policy of thorough Germanization. After 1945 this was succeeded by Polonization as Moscow granted most of the German territories east of the Oder-Neisse line (including almost the whole of Silesia) to Poland. In consequence, almost the entire Lower Silesia...