Silesian

The Silesians are Lechitic West Slavs of Silesia in the Oder basin, whose speech sits between Polish and Czech. White Croats settled there in the sixth century; the Bavarian Geographer of 830 records the Ślężanie, named after the Ślęża cult mountain. After Great Moravia and Bohemia, Mieszko I folded the lands into the Polish state, which founded Wrocław's diocese in 1000.

The fragmentation of 1177 split Silesia into Piast duchies; in 1241 the Mongols slew Duke Henry II the Pious at Legnica. From the thirteenth century German Ostsiedlung settlers founded Magdeburg-law towns and made Wrocław bilingual; the Book of Henryków preserved the oldest surviving Polish sentence. The duchies accepted Bohemian suzerainty in 1327–1348 and passed to the Habsburgs in 1526.

Frederick II of Prussia seized most of Silesia in 1742, and the Congress of Vienna in 1815 confirmed it as a Prussian province. Upper Silesia became coal and iron country, its Slavic villagers keeping their Polish-like dialect into the nineteenth century.