The Holocaust (from the Greek ὁλόκαυστος holókaustos: hólos, "whole" and kaustós, "burnt"),also known as the Shoah (Hebrew:השואה, HaShoah, "the catastrophe"), was a genocide in which approximately six million Jews were killed by Adolf Hitler's Nazi regime and its collaborators. Some historians use a definition of the Holocaust that includes the additional five million non-Jewish victims of Nazi mass murders, bringing the total to approximately eleven million. Killings took place throughout Nazi Germany and German-occupied territories.

From 1941 to 1945, Jews were systematically murdered in a genocide, one of the largest in history, and part of a broader aggregate of acts of oppression and killings of various ethnic and political groups in Europe by the Nazi regime. Every arm of Germany's bureaucracy was involved in the logistics and the carrying out of the genocide, turning the Third Reich into "a genocidal state".Other victims of Nazi crimes included Romanis, ethnic Poles and other Slavs,Soviet POWs, communists, homosexuals, Jehovah's Witnesses and the mentally and physically disabled.^[7] In total, approximately 11 million people were killed, including approximately one million Jewish children.Of the nine million Jews who had resided in Europe before the Holocaust, approximately two-thirds were killed. A network of about 42,500 facilities in Germany and German-occupied territories were used to concentrate, confine, and kill Jews and other victims.Over 200,000 people are estimated to have been Holocaust perpetrators.

The persecution and genocide were carried out in stages, culminating in what was termed the "Final Solution to the Jewish Question" (die Endlösung der Judenfrage), the agenda to exterminate Jews in Europe. Initially the German government passed laws to exclude Jews from civil society, most prominently theNuremberg Laws of 1935. A network of concentration camps was established starting in 1933 and ghettos were established following the outbreak of World War II in 1939. In 1941, as Germany conquered new territory in eastern Europe, specialized paramilitary units called Einsatzgruppen were used to murder around two million Jews and "partisans", often in mass shootings. By the end of 1942, victims were being regularly transported by freight trains to specially builtextermination camps where, if they survived the journey, most were systematically killed in gas chambers. The campaign of murder continued until theend of World War II in Europe in April–May 1945.

Overall, Jewish armed resistance was limited. The most notable exception was the Warsaw Ghetto Uprising of 1943, when thousands of poorly-armed Jewish fighters held the Waffen-SS at bay for four weeks. An estimated 20,000 to 30,000 Jewish partisans actively fought against the Nazis and their collaborators in Eastern Europe. French Jews were also highly active in the French Resistance, which conducted a guerilla campaign against the Nazis and Vichy French authorities. In total, over a hundred armed Jewish uprisings took place.

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