After the December 1941 defeat of the German army in its attempt to take Moscow and the entry of the United States into World War II on December 11, the German authorities understood that Germany would have to fight a long war. Responding to increasingly acute labor shortages and the need to produce armaments, machinery, airplanes, and ships to replace German losses, the SS established more SS-owned firms. It also signed contracts with state and private firms to produce goods and provide labor for the German armaments and related industries.
A famous example of cooperation between the SS and private industry was the I.G. Farben company's establishment of a synthetic rubber plant in 1942 at Auschwitz III (Monowitz). The incarceration of increasing numbers of people in the concentration camps assured at least the quantity of the labor supply even as the brutality of the regimen inside the camps depleted the number of available laborers. The SS used gas chambers and other means to "weed out" prisoners who were no longer able to work.
During 1942-1944, hundreds of subcamps were established for each concentration camp. Subcamps were located in or near factories or sites for the extraction of raw materials. For example, Wiener Neudorf, a subcamp of Mauthausen established in 1943, was located near an airplane factory on the east side of Vienna, Austria; Sosnowitz was established in the vicinity of a coal mine as a subcamp of Auschwitz III/Monowitz; prisoners incarcerated at Dora-Mittelbau worked under brutal conditions in underground factories for the production of rockets. Central SS authorities tried to induce camp commandants to focus their efforts on keeping the prisoners alive, if only to serve the German war effort. However, few of the commandants took these instructions seriously and none were concerned about changing the murderous culture of the camps.
During the last year of the war, as the Germans retreated into the Reich itself, the concentration...