Teschen

Teschen is the German name for the town of Cieszyn, located in the border region of Silesia on the Olza River, opposite Český Těšín in the Czech Republic. The name also denotes the historic Duchy of Teschen (Księstwo cieszyńskie), a medieval Silesian principality that arose in the late 13th century during the fragmentation of Polish Piast lands. Its capital was the town of Cieszyn, and it was administered as part of the Bohemian Crown lands from the 14th century and later became part of the Habsburg Monarchy in the 16th century. The duchy persisted as a semi-sovereign entity within larger dynastic realms until the 18th century reforms and the reshaping of Silesia under Habsburg rule.

After the dissolution of Austria-Hungary at the end of World War I, Teschen Silesia was disputed between Poland and Czechoslovakia. In 1920, the Spa Conference divided the region along the Olza River, with the western part around Cieszyn remaining in Poland and the eastern part around Český Těšín becoming part of Czechoslovakia. In 1938, Poland temporarily annexed the Trans-Olza area following the Munich Agreement, and after World War II the border was re-established along the Olza, leaving the area split between Poland and Czechoslovakia (and later the Czech Republic).

Today, Teschen refers to the cross-border Cieszyn Silesia region, anchored by the twin towns of Cieszyn (Poland) and Český Těšín (Czech Republic). The area is noted for its mixed Polish and Czech heritage, bilingual cultural remnants, and cross-border economic and transport links.