East Upper Silesia

East Upper Silesia (German: Ostoberschlesien) is a term denoting the easternmost extremity of Silesia, the eastern part of the Upper Silesian region around the city of Katowice (German: Kattowitz). The term is used primarily to denote those areas that became part of the Second Polish Republic on 20 June 1922, as a consequence of the post-World War I Treaty of Versailles. Prior to World War II, the Second Polish Republic administered the area as Autonomous Silesian Voivodeship. East Upper Silesia was also known as Polish (Upper) Silesia, and the German (Upper) Silesia was known as West Upper Silesia.

East Upper Silesia was annexed by Nazi Germany along with other Polish areas following the invasion of Poland in 1939, which triggered the outbreak of World War II. Until 1941, the region was administered as Regierungsbezirk Kattowitz, the easternmost government region of the Silesia Province. From 1941 to 1945, it was part of the Upper Silesia Province. Under Nazi rule, Upper Silesia included the cities of Beuthen, Gleiwitz, Hindenburg in Oberschlesien, Kattowitz, and Königshütte. It also contained the rural districts (Landkreis) of Bendsburg, Beuthen-Tarnowitz, Bielitz, Kattowitz, Krenau, Ilkenau, Pless, Rybnik, Saybusch, Teschen, and Toszek-Gleiwitz.

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