According to the racial ideology, National Socialism saw Jews as the main foes of the German people. The Laws of Nuremberg, enacted in 1935, refused Jews admittance to German citizenship and forbad any marriage between Jews and Germans ("Law to protect German Blood"). At first, Jews were deported as "undesirable aliens" or sent to internment camps. In the so-called "Cristal Night", November 9, 1938, some 30.000 Jews were deported to concentration camps. Terror against Jews was intended to accelerate their emigration.
At the climax of their military successes, the Nazis started a war of extermination against the internal "race enemies" - the Jews. The worst consequence of that racist policy was the mass murder, genocide. In summer 1941, Heinrich Himmler ordered the commander of Auschwitz, Rudolf Höss, to prepare plans for mass extermination of Jews and to reconstruct the Auschwitz concentration camp in order to "solve the Jewish Question". The first attempts with Cyclone - B gas took place in September 1941 in Auschwitz.
Reinhard Heydrich, head of the RSHA, started to prepare an "Overall Solution of the Jewish Question", according to an order by Hermann Gšring. The Nazis aimed at the deportation of 11 million European Jews into the extermination camps. That mass extermination was coordinated between different authorities at the Wannseekonferenz in Berlin of January 20, 1942. All people of Jewish origins should be looked for between West and East, North and South and sent to the extermination camps. Since early 1942, transports with Jews rolled to the extermination camps - such as Kulmhof (Chelmno),Majdanek, Belzec, Sobibor, Treblinka, Auschwitz-Birkenau, etc.
A reconstructed farm house was used by the SS to gas Jews in Auschwitz-Birkenau. The first transports, coordinated by Adolf Eichmann, reached Auschwitz on March 26, 1942, so that a second farm house had to be reconstructed for mass-gassing. In July 1942, Himmler ordered an extension of Birkenau for 200.000 prisoners and the construction of four crematories and gas chambers.
According to plans of the company "Hoch- und Tiefbau AG Kattowitz", four crematories and gas chambers were put in operation between March 22 and June 5, 1943. The crematories and gas chamber equipments were delivered by the Erfurt firm J.A. Topf & sons. Already in October 1942, Himmler had given order to transfer all Jews to Auschwitz or Majdanek. The biggest action happened between May 8 and July 29, 1944 - Rudolf Hš§ was to gas more than 400.000 Hungarian Jews on Himmlers command. On some days, up to 24.000 people were murdered, their bodies burnt on funeral piles because of the lack of capacity of the crematories.