The Holocaust, also known as the Shoah, was the World War II genocide of the European Jews. Between 1941 and 1945, across German-occupied Europe, Nazi Germany and its collaborators systematically murdered some six million Jews, around two-thirds of Europe's Jewish population.

The murders were carried out in pogroms and mass shootings; by a policy of extermination through labor in concentration camps; and in gas chambers and gas vans in German extermination camps, chiefly Auschwitz, Bełżec, Chełmno, Majdanek, Sobibór, and Treblinka in occupied Poland. Germany implemented the persecution in stages.

Following Adolf Hitler's appointment as Chancellor on 30 January 1933, the regime built a network of concentration camps in Germany for political opponents and those deemed "undesirable", starting with Dachau on 22 March 1933. After the passing of the Enabling Act on 24 March, which gave Hitler plenary powers, the government began isolating Jews from civil society, which included a boycott of Jewish businesses in April 1933, and enacting the Nuremberg Laws in September 1935. On 9–10 November 1938, eight months after Germany annexed Austria, Jewish businesses and other buildings were ransacked, smashed or set on fire throughout Germany and Austria during what became known as Kristallnacht (the "Night of Broken Glass"). After Germany invaded Poland in September 1939, triggering World War II, the regime set up ghettos to segregate Jews from the rest of the population.

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