Throughout the Middle Ages in Europe, Jews were subjected to antisemitism based on Christian theology, which blamed them for killing Jesus. Even after the Reformation, Catholicism and Lutheranism continued to persecute Jews, accusing them of blood libels and subjecting them to pogroms and expulsions. The second half of the 19th century saw the emergence in the German empire and Austria-Hungary of the völkisch movement, which was developed by such thinkers as Houston Stewart Chamberlain and Paul de Lagarde. The movement embraced a pseudo-scientific racism that viewed Jews as a race whose members were locked in mortal combat with the Aryan race for world domination. These ideas became commonplace throughout Germany, with the professional classes adopting an ideology that did not see humans as racial equals with equal hereditary value. Although the völkisch parties had support in elections at first, by 1914 they were no longer influential. This did not mean that antisemitism had disappeared; instead it was incorporated into the platforms of several mainstream political parties.
Begin thought settling the score with Mengele would show Palestinian leaders (and the Israeli public) that they would have to pay a price for harming Israelis. His attitude was reflected in a message he sent to President Ronald Reagan when he sent the Israeli Army into Lebanon in 1982, saying that he felt as if “I have sent an army to Berlin to wipe out Hitler in the bunker.”
Most Holocaust historians define the Holocaust as the enactment, between 1941 and 1945, of the German state policy to exterminate the European Jews.[a] In Teaching the Holocaust (2015), Michael Gray, a specialist in Holocaust education, offers three definitions: (a) "the persecution and murder of Jews by the Nazis and their collaborators between 1933 and 1945", which views the events of Kristallnacht in Germany in 1938 as an early phase of the Holocaust; (b) "the systematic mass murder of the Jews by the Nazi regime and its collaborators between 1941 and 1945", which acknowledges the shift in German policy in 1941 toward the extermination of the Jewish people in Europe; and (c) "the persecution and murder of various groups by the Nazi regime and its collaborators between 1933 and 1945", which includes all the Nazis' victims. The third definition fails, Gray writes, to acknowledge that only the Jewish people were singled out for annihilation.
The industrialization and scale of the murder was unprecedented. Killings were systematically conducted in virtually all areas of occupied Europe—more than 20 occupied countries. Close to three million Jews in occupied Poland and between 700,000 and 2.5 million Jews in the Soviet Union were killed. Hundreds of thousands more died in the rest of Europe. Victims were transported in sealed freight trains from all over Europe to extermination camps equipped with gas chambers. The stationary facilities grew out of Nazi experiments with poison gas during the Aktion T4 mass murder ("euthanasia") programme against the disabled and mentally ill, which began in 1939. The Germans set up six extermination camps in Poland: Auschwitz II-Birkenau (established October 1941); Majdanek (October 1941); Chełmno (December 1941); and the three Operation Reinhard camps, Belzec, Sobibor, and Treblinka, in 1942. A seventh death camp, Maly Trostenets, was established near Minsk in Belarus, then part of the Reichskommissariat Ostland. Discussions at the Wannsee Conference in January 1942 made it clear that the German "final solution of the Jewish question" was intended eventually to include Britain and all the neutral states in Europe, including Ireland, Switzerland, Turkey, Sweden, Portugal, and Spain.
In his monograph, The Origins Of The Final Solution: The Evolution of Nazi Jewish Policy, September 1939 – March 1942, Christopher Browning argues that Nazi policy toward the Jews was radicalized twice: in September 1939, when the invasion of Poland implied policies of mass expulsion and massive loss of Jewish lives; and in spring 1941, when preparation for Operation Barbarossa involved the planning of mass execution, mass expulsion, and starvation – to dwarf what had happened in Jewish Poland.
In 1942, Auschwitz II (Birkenau), originally intended to house slave laborers, began to be used instead as a combined labor camp and extermination camp. Prisoners were transported there by rail from all over German-occupied Europe, arriving in daily convoys. By July 1942, SS doctors were conducting "selections" where incoming Jews were segregated, and those considered able to work were admitted into the camp while those deemed unfit for labor were immediately killed in the gas chambers. The arrivals that were selected to die, about three-quarters of the total,[a] included almost all children, women with small children, pregnant women, all the elderly, and all of those who appeared (in a brief and superficial inspection by an SS doctor) to be not completely fit and healthy.