Cottbus or Chóśebuz is a university city and the second-largest city in the German state of Brandenburg after the state capital of Potsdam. With around 98,000 inhabitants, it is the most populous city in Lusatia. Cottbus lies in the Sorbian settlement area of Lower Lusatia, and is the second-largest city on the River Spree after Berlin, from which it is situated around 125 km (78 mi) upstream. The city is located on the shores of Cottbus Eastern Lake, which will be Germany's largest artificial lake by surface area when flooding is completed.

Lusatia is a historical region in Central Europe, territorially split between Germany and Poland. Lusatia stretches from the Bóbr and Kwisa rivers in the east to the Pulsnitz and Black Elster rivers in the west, and is located within the German states of Saxony and Brandenburg as well as in the Polish voivodeships of Lower Silesia and Lubusz. Major rivers of Lusatia are the Spree and the Lusatian Neisse, which defines the border between Germany and Poland. The Lusatian Mountains of the Western Sudetes separate Lusatia from Bohemia in the south. Lusatia is traditionally divided into Upper Lusatia, the hilly southern part, and Lower Lusatia, the flat northern part.