Silesia (Polish Ślask; German Schlesien; Czech Slezsko), historic region of Central Europe, mostly in what is now southwestern Poland, comprising the provinces of Katowice, Opole, Wrocław, Wałbrzych, Jelenia Góra, and Legnica and part of Zielona Góra. Silesia also included sections of present-day north central Czech Republic and of the states of Brandenburg and Saxony in eastern Germany. In the Middle Ages, Silesia was settled by a mixed German and Polish population. It became part of the kingdom of Poland in the 11th century and was acquired by Bohemia in the 14th century. The region was ruled by the Austrian Habsburgs from 1526 to 1742, when most of it was annexed by Prussia. In the 19th century it became a center for the textile and coal-mining industries. After World War II (1939-1945), almost all of Prussian Silesia reverted to Poland, and the German population was expelled.