From 1933 to 1945, Nazi Germany operated more than a thousand concentration camps (German: Konzentrationslager[a]), including subcamps[b] on its own territory and in parts of German-occupied Europe.
Initially, most prisoners were members of the Communist Party of Germany, but as time went on different groups were arrested, including "habitual criminals", "asocials", and Jews.
Many prisoners held by Germany died as a result of intentional withholding of food and dangerous working conditions in violation of the 1907 Hague Convention.
[11] The concentration camp system arose in the following months due to the desire to suppress tens of thousands of Nazi opponents in Germany.
The Reichstag Fire Decree eliminated the right to personal freedom enshrined in the Weimar Constitution and provided a legal basis for detention without trial.
[13][12] There was no national system;[15] camps were operated by local police, SS, and SA, state interior ministries, or a combination of the above.
[18] In May 1934, Lichtenburg was taken over by the SS from the Prussian bureaucracy, marking the beginning of a transition set in motion by Heinrich Himmler, then chief of the Gestapo (secret police).
[21] Believing Nazi Germany to be imperiled by internal enemies, Himmler called for a war against the "organized elements of sub-humanity", including communists, socialists, Jews, Freemasons, and criminals.
[24] According to SS chief Heinrich Himmler, the "criminal" prisoners at concentration camps needed to be isolated from society because they had committed offenses of a sexual or violent nature.
The SS company German Earth and Stone Works (DEST) was set up with funds from Speer's agency for exploiting prisoner labour to extract building materials.
After the Kristallnacht pogrom in November 1938, 26,000 Jewish men were deported to concentration camps following mass arrests, overwhelming the capacity of the system.
These prisoners were subject to unprecedented abuse leading to hundreds of deaths – more people died at Dachau in the four months after Kristallnacht than in the previous five years.
[30][31] At the end of August 1939, prisoners of Flossenbürg, Sachsenhausen, and other concentration camps were murdered as part of false flag attacks staged by Germany to justify the invasion of Poland.
[35] This expansion was driven by the demand for forced labor and later the invasion of the Soviet Union; new camps were sent up near quarries (Natzweiler and Gross-Rosen) or brickworks (Neuengamme).
[34][36] In April 1941, the high command of the SS ordered the murder of ill and exhausted prisoners who could no longer work (especially those deemed racially inferior).
[42][43] During the second half of the war, Auschwitz swelled in size – fueled by the deportation of hundreds of thousands of Jews – and became the center of the camp system.
[50] In 1942, the IKL was subordinated to the SS Main Economic and Administrative Office (SS-WVHA) to improve the camps' integration into the war economy.
[52] Towards the end of the 1930s, the SS-Totenkopfverbande expanded its operations and set up military units, which followed the Einsatzgruppen death squads and massacred Polish Jews as well as Soviet prisoners of war.
[56] Most of the camp SS leadership was middle-class and came from the war youth generation [de], who were hard-hit by the economic crisis and feared decline in status.
[58] Perpetration by this leadership was based on their tight social bonds, a perceived common sense that the aims of the system were good, as well as the opportunity for material gain.
[50] More than 100,000 Soviet prisoners of war and smaller groups from other nationalities were transferred to the concentration camps in direct violation of the Geneva Convention.
[50] Jews, Slavic prisoners, and Spanish Republicans were targeted for especially harsh treatment which led to a high mortality rate during the first half of the war.
[70] During the first years of the camps, unemployment was high and prisoners were forced to perform economically valueless but strenuous tasks, such as farming on moorland (such as at Esterwegen).
[71] In the years before World War II, quarrying and bricklaying for the SS company DEST played a central role in prisoner labor.
[80] Nazi propaganda demonized the prisoners as race traitors, sexual degenerates, and criminals and presented the camps as sites of re-education.
[83] These subcamps, often established in town centers in such locations as schools, restaurants, barracks, factory buildings, or military camps, were joint ventures between industry and the SS.
An increasing number of German civilians interacted with the camps: entrepreneurs and landowners provided land or services, doctors decided which prisoners were healthy enough to continue working, foremen oversaw labor deployments, and administrators helped with logistics.
[89] Historian Robert Gellately argues that "the Germans generally turned out to be proud and pleased that Hitler and his henchmen were putting away certain kinds of people who did not fit in, or who were regarded as 'outsiders', 'asocials', 'useless eaters', or 'criminals'".
[90] According to historian Karola Fings, fear of arrest did not undermine public support for the camps because Germans saw the prisoners rather than the guards as criminals.
[107] The concentration camps have been the subject of historical writings since Eugen Kogon's 1946 study, Der SS-Staat [de] ("The SS State").