COSEL  , or KosEL, a

town of Germany, in the Prussian province of Silesia, at the junction of the Klodnitz' and the Oder, 29 M . S.E. of Oppeln by rail . Pop . (1905) 7085 . It has an Evangelical and a Roman Catholic church, an old chateau and a grammar-school (Progymnasium) . Its industries are of some importance, including a manufactory of cellulose (employing 1200 hands), steam saw- and flour-mills and a petroleum refinery . There is a lively trade by river . The first record of Cosel dates from 1286 . From 1306 to 1359 it was the seat of an independent duchy held by a cadet line of the dukes of Teschen . In 1532 it fell to the emperor, was several times besieged during the Thirty Years' War, and came into Prussian possession by the treaty of Breslau in 1942 . Frederick IL converted it into a fortress, which was besieged in vain by the Austrians in 1758, 1759, 1760 and 1762 . In 1807 it withstood another siege, by the Bavarian allies of Napoleon .

The fortifications were razed and their site converted into promenades in 1894 .