Between the winter of 1941 and the autumn of 1944, more than 3 million European Jews died in one of the nazi extermination camps. In addition to the six large extermination camps (Auschwitz-Birkenau, Treblinka, Sobibor, Majdanek, Belzec, and Chelmno), which were part of the 'SS state' under leadership of Heinrich Himmler, thousands of other small and large camps existed before and during the war: concentration camps, prison camps, transit camps, labour camps, internment camps, etc. Not only Jews, but also prisoners of war, political opponents, Sinti and Roma, homosexuals, Jehovah's Witnesses, 'antisocial' people, 'criminals', people with a disability, and other 'undesired elements' of society were placed in the camps, often without any due process. In Germany alone, approximately 3.5 million people spent short or long periods in a camp or prison between 1933 and 1945. Prisoners often died as a result of severe malnutrition, contagious diseases, difficult forced labour, poor medical care, and exhaustion. Prisoners who could no longer stand the inhuman camp existence committed suicide.