(in Polish, Śląsk; in Czech, Slezsko; in German, Schlesien), a historic Slavic region along the upper and middle reaches of the Oder (Odra) River. Silesia was part of Poland from the tenth century; in the 12th and 13th centuries it was divided into numerous appanage principalities. In the first third of the 14th century the principalities came under the rule of the Luxembourgs, and in 1526, the Hapsburgs established their rule over Silesia, with the exception of three principalities that had been reunited with Poland in the late 15th century.
During the War of the Austrian Succession (1740–48), most of Silesia was seized by Prussia. Subsequently, the germanization of Silesia, begun in the Middle Ages, grew more intense. However, even as late as the 19th century a considerable part of Silesia’s population retained its Polish heritage. After 1742, the Austrian Hapsburgs held only the southern principalities of Silesia (Opava, Cieszyn), and after the collapse of Austria-Hungary in 1918 these principalities became part of Czechoslovakia.
Coal mining and metallurgy developed in Upper Silesia in the early 19th century; uprisings of Silesian weavers took place in 1793 and 1844. After the restoration of the Polish state in 1918, the workers of Silesia fought for reunification with Poland. There were uprisings in 1919, 1920, and 1921, but because of the opposition of the great imperialist powers, only one-third of Upper Silesia passed to Poland (1922). In 1938–39, all of Silesia came under the rule of fascist Germany; it was liberated from the Hitlerites by the Soviet Army in 1945. The Potsdam Conference of 1945 established the Oder-Neisse line as the western frontier of Poland, and most of Silesia consequently became part of Poland.
The part of Silesia in the People’s Republic of Poland includes the województwa of Opole, Wrocław, Wałbrzych, and Legnica, the greater part of the województwo of Katowice, and parts of the województwa of Jelenia Góra, Zielona Góra, Lesz-no, and Bielsko-Białe (according to the administrative territorial division of June 1, 1975). Czech Silesia is part of the province of North Moravia of the Czechoslovak Socialist Republic.
I. S. MILLER [23–1068–]