a town of Germany, in the kingdom of Prussia, on the Spree, 72 m. S.E. of Berlin by the main railway to Gorlitz, and at the intersection of the lines Halle-Sagan and GrossenhainFrankfort-on-Oder. Pop. (1905) 46,269. It has four Protestant churches, a Roman Catholic church and a synagogue. The chief industry of the town is the manufacture of cloth, which has flourished here for centuries and now employs more than 6000 hands. Wool-spinning, cotton-spinning and the manufacture of tobacco, machinery, beer, brandy, &c., are also carried on. The town is also a considerable trading centre, and is the seat of a chamber of commerce and of a branch of the Imperial Bank (Reichsbank). In the Stadtwald, close to the town, is a women's hospital for diseases of the lungs, a government institution in connexion with the state system of insurance against incapacity and old age. At Branitz, a neighbouring village, are the magnificent château and park of Prince Piickler-Muskau.
At one time Cottbus formed an independent lordship of the Empire, but in 1462 it passed by the treaty of Guben to Brandenburg. From 1807 to 1813 it belonged to the kingdom of Saxony.