Commission for the Determination of Place Names

The Commission for the Determination of Place Names (Polish: Komisja Ustalania Nazw Miejscowości) was a commission of the Polish Department of Public Administration, founded in January 1946. Its mission was the establishment of toponyms for places, villages, towns and cities in the former eastern territories of Germany (then known in Poland as the Regained Territories).

According to the decisions of the Potsdam Conference most of the former German territories east of the Oder-Neisse line were placed under Polish administration and most of the remaining German population was expelled. Some of those territories had historical ties with Poland, dating to the medieval fragmentation of Poland in the Duchy of Silesia, but were also populated by German-speaking inhabitants for many centuries.

According to the 1939 German census, the territories were inhabited by 8,855,000 people, including a Polish minority in the territories' easternmost parts. The Polish minority included Masurs in Masuria (former southern East Prussia), Kashubians and Slovincians in Pomerania, and Silesians in Upper Silesia - these groups were referred to as "" after the war, and used to prove a "Polishness" of the territories. While the German census placed the number of Polish-speakers and bilinguals below 700,000 people, Polish demographers have estimated that the actual number of Poles in the former German East was between 1.2 and 1.3 million. In the 1.2 million figure, approximately 850,000 were estimated for the Upper Silesian regions, 350,000 for southern East Prussia (Masuria) and 50,000 for the rest of the territories.

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