Along with the majority of ethnic German East Prussians, many Masurians fled to western Germany as the Soviet Red Army approached East Prussia in 1945 in the final European campaigns of World War II. The post-war Potsdam Conference placed Masuria - and the rest of southern East Prussia - under Polish administration. Many Masurians who were classified as Germans were expelled with military force. After 1956 many who had remained in Poland emigrated to West Germany, approximately 5,000 Masurians still lived in the area, many of them as members of the German minority. Speculations about the reasons of this emigration vary from the economic situation and the undemocratic - communist - system in Poland to the shrinking prospect of a return of Masuria to Germany.