 During World War II Jasień was the location of the Nazi German slave labour camp "KL Gassen", one of nearly one hundred subcamps of Gross-Rosen concentration camp for Poles, Soviet prisoners of war, Czechs, and even Frenchmen, making warplane parts for Focke-Wulf AG.The camp, with around 700 acutely malnourished prisoners, operated from August 1944 until 13 February 1945, when the remaining workforce was sent on a death march to KL Buchenwald ahead of the Soviet advance.See twin towns of Gmina Jasień.