The Duchy of Cieszyn (Polish: Księstwo Cieszyńskie) or Duchy of Teschen (German: Herzogtum Teschen) or Duchy of Těšín (Czech: Těšínské knížectví, Latin: Ducatus Tessinensis) was an autonomous Silesian duchy centered on Teschen (Cieszyn) in Upper Silesia. After the feudal division of Poland it was split off in 1281 and ruled by Silesian dukes from the Piast dynasty since 1290. The Duchy of Teschen was also composed of smaller Duchies at various points of time, such as Oświęcim which was split off around 1315, or Zator which in turn split from the Duchy of Oświęcim in 1454.
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