After its defeat in World War I, Germany was humiliated by the Versailles Treaty, which reduced its prewar territory, drastically reduced its armed forces, demanded the recognition of its guilt for the war, and stipulated it pay reparations to the allied powers. With the German Empire destroyed, a new parliamentary government called the Weimar Republic was formed. The republic suffered from economic instability, which grew worse during the worldwide depression after the New York stock market crash in 1929. Massive inflation followed by very high unemployment heightened existing class and political differences and began to undermine the government.
Their decency exposed them to the dangers of discovery and denunciation. If caught, they faced torture, deportation to concentration camps, or execution. Their behavior was atypical even in their own communities, where the attitude of the majority was characterized by inertia, indifference, and open complicity in the persecution and mass murder of Europe’s Jews.
“You want to know about my motivation, don't you? Well. It is the kind of sentiments anyone would have when he actually sees refugees face to face, begging with tears in their eyes. He just cannot help but sympathize with them. Among the refugees were the elderly and women. They were so desperate that they went so far as to kiss my shoes, Yes, I actually witnessed such scenes with my own eyes. Also, I felt at that time, that the Japanese government did not have any uniform opinion in Tokyo. Some Japanese military leaders were just scared because of the pressure from the Nazis; while other officials in the Home Ministry were simply ambivalent.
The biblical term shoah (Hebrew: שׁוֹאָה), meaning "destruction", became the standard Hebrew term for the murder of the European Jews, first used in a pamphlet in 1940, Sho'at Yehudei Polin ("Sho'ah of Polish Jews"), published by the United Aid Committee for the Jews in Poland.[11] On 3 October 1941 the cover of the magazine The American Hebrew used the phrase "before the Holocaust", apparently to refer to the situation in France,[12] and in May 1943 The New York Times, discussing the Bermuda Conference, referred to the "hundreds of thousands of European Jews still surviving the Nazi Holocaust".[13] In 1968 the Library of Congress created a new category, "Holocaust, Jewish (1939–1945)".[14] The term was popularized in the United States by the NBC mini-series Holocaust (1978), about a fictional family of German Jews,[15] and in November 1978 the President's Commission on the Holocaust was established.[16] As non-Jewish groups began to include themselves as Holocaust victims too, many Jews chose to use the terms Shoah or Churban instead.[12][g] The Nazis used the phrase "Final Solution to the Jewish Question" (German: die Endlösung der Judenfrage).[18]
The murder industry began in the Chelmno camp, built in December 1941. Work was carried out in special trucks, where the victims were asphyxiated by exhaust fumes, a method that had been tried before on those whose lives were deemed useless (the “Euthanasia Pro­gram”). From September 1939, about 100,000 “Aryan” Germans were assassinated in this manner, in what was named “Operation T4.” Two years later, the personnel responsible for the “euthanasia” program were called upon to apply their expertise to murdering Jews. In the single camp of Chelmno, 150,000 human beings were gassed to death, most of them brought to the camp from annexed territories, the Warthegau district of western Poland and the Lodz Ghetto.
The geographical patterns of local hostility to Jews influenced receptivity to their rescue. Thus, western Europe (France, Belgium, and the Netherlands), Scandinavia (Denmark and Finland), and southern Europe (Italy and Greece) adapted rapidly to the problems of hiding and rescuing Jews, whereas eastern and central Europe (Poland, the Ukraine, and Austria) remained a more hostile environment to rescue efforts.
Antisemitism, the new racist version of the old Jew-hatred, viewed the Jews as not simply a religious group but as members of a 'Semitic race', which strove to dominate its 'Aryan' rivals. Among the leading ideologues of this theory were a French aristocrat, the Comte Joseph de Gobineau, and an Englishman, Houston Stewart Chamberlain. Antisemitism proved a convenient glue for conspiracy theories - since Jews were involved in all sorts of ventures and political movements, they could be accused of manipulating all of them behind the scenes. Thus Jews were held responsible for Communism and capitalism, liberalism, socialism, moral decline, revolutions, wars, plagues and economic crises. As the Jews had once been demonised in medieval Europe, so the new antisemites (including many Christians) found new, secular ways of demonising them.
Because they refused to pledge allegiance to the Nazi party or serve in the military, Jehovah's Witnesses were sent to concentration camps, where they were identified by purple triangles and given the option of renouncing their faith and submitting to the state's authority.[447] The United States Holocaust Memorial Museum estimates that between 2,700 and 3,300 were sent to the camps, where 1,400 died;[411] in The Holocaust Encyclopedia (2001), Sybil Milton estimates that 10,000 were sent and 2,500 died.[412] According to German historian Detlef Garbe, "no other religious movement resisted the pressure to conform to National Socialism with comparable unanimity and steadfastness."[448]

The Nazis established ghettos in occupied Poland. Polish and western European Jews were deported to these ghettos. During the German invasion of the Soviet Union in 1941, mobile killing squads (Einsatzgruppen) began killing entire Jewish communities. The methods used, mainly shooting or gas vans, were soon regarded as inefficient and as a psychological burden on the killers.

When Germany invaded Poland in September 1939, it gained control of about 2 million Jews in the occupied territory. The rest of Poland was occupied by the Soviet Union, which had control of the rest of Poland's pre-war population of 3.3–3.5 million Jews.[141] German plans for Poland included expelling gentile Poles from large areas, confining Jews, and settling Germans on the emptied lands.[142] The Germans initiated a policy of sending Jews from all territories they had recently annexed (Austria, Czechoslovakia, and western Poland) to the central section of Poland, which they called the General Government. There, the Jews were concentrated in ghettos in major cities,[143] chosen for their railway lines to facilitate later deportation.[144] Food supplies were restricted, public hygiene was difficult, and the inhabitants were often subjected to forced labor.[145] In the work camps and ghettos, at least half a million Jews died of starvation, disease, and poor living conditions.[146] Jeremy Black writes that the ghettos were not intended, in 1939, as a step towards the extermination of the Jews. Instead, they were viewed as part of a policy of creating a territorial reservation to contain them.[147][l]
Reichsführer-SS Heinrich Himmler visited Auschwitz-Birkenau on July 17 and 18, 1942 and watched the gassing of 449 women and children in Bunker No. 1, according to his biographer Peter Padfield. On July 23, 1942, Himmler ordered the quarantine of the Birkenau camp because of a typhus epidemic, but the gassing of the Jews continued. On December 28, 1942, Himmler issued an order that the death rate "must be reduced at all costs" according to document 2172-PS that was introduced at the Nuremberg IMT. He meant the death rate from typhus; the gassing of the Jews did not stop.

The St. Louis arrived in Havana harbor on May 27th. Of the 937 passengers on board, only 28 passengers were allowed into Cuba. 22 of these passengers were Jewish and had valid U.S. visas, 4 were Spanish citizens and 2 were Cuban nationals, all with valid documents. This story gained a lot of publicity; it was spread throughout Europe and the United States. The U.S. newspapers reported the story compassionately, but only a handful suggested that the refugees should come to the United States. The United States government decided not to take the steps to permit the passengers into the country.
Finland was pressured in 1942 to hand over its 150–200 non-Finnish Jews to Germany. After opposition from the government and public, eight non-Finnish Jews were deported in late 1942; only one survived the war.[173] Japan had little antisemitism in its society and did not persecute Jews in most of the territories it controlled. Jews in Shanghai were confined, but despite German pressure they were not killed.[174]
There is no postwar institution specializing in either World War II or the Holocaust that has collected systematic data about the righteous or about Christian-Jewish relations during the war years. Postwar historiography has given scant attention to this subject, except for biographies of heroes like Raoul Wallenberg in Budapest. Individual episodes are recorded in numerous published memoirs or hidden within the histories of the Jewish communities under German occupation. Others are found in some survivor testimonies, oral histories, and depositions.
In May 1944, Himmler told senior army officers that, "The Jewish question has been solved in Germany and in the countries occupied by Germany. It has been solved uncompromisingly, as was appropriate in view of the struggle in which we were engaged for the life of our nation." Himmler explained that it was important that even women and children had to die, so that no "hate-filled avengers" would be able to confront our children and grandchildren.[128]
On 6 January 1942, the Soviet Minister of Foreign Affairs, Vyacheslav Molotov, sent out diplomatic notes about German atrocities. The notes were based on reports about bodies surfacing from poorly covered graves in pits and quarries, as well as mass graves found in areas the Red Army had liberated, and on witness reports from German-occupied areas.[335] The following month, Szlama Ber Winer escaped from the Chełmno concentration camp in Poland, and passed detailed information about it to the Oneg Shabbat group in the Warsaw Ghetto. His report, known by his pseudonym as the Grojanowski Report, had reached London by June 1942.[288][336] Also in 1942, Jan Karski sent information to the Allies after being smuggled into the Warsaw Ghetto twice.[337][s] On 27 April 1942, Vyacheslav Molotov sent out another note about atrocities.[335] In late July or early August 1942, Polish leaders learned about the mass killings taking place inside Auschwitz. The Polish Interior Ministry prepared a report, Sprawozdanie 6/42,[340] which said at the end:
"... Believe me, I'd like to listen, but it doesn't work, because if I'm quiet and serious, everyone thinks I'm putting on a new act and I have to save myself with a joke, and then I'm not even talking about my own family, who assume I must be ill, stuff me with aspirins and sedatives, feel my neck and forehead to see if I have a temperature, ask about my bowel movements and berate me for being in a bad mood, until I just can't keep it up any more, because when everybody starts hovering over me, I get cross, then sad, and finally end up turning my heart inside out, the bad part on the outside and the good part on the inside, and keep trying to find a way to become what I'd like to be and what I could be if ... if only there were no other people in the world."
The Mossad was still a young agency, short of resources and manpower. Moreover, as Aharoni later put it in testimony for the Mossad’s history department, “When Isser began dealing with something, he dealt only with that.” In addition, the agency had been blindsided, knowing nothing about the German scientists and the missiles they were building for Israel’s biggest enemy. Harel mobilized the entire agency to deal with it.
In June 1941 Germany attacked the Soviet Union and began the "Final Solution." Four mobile killing groups were formed called Einsatzgruppen A, B, C and D. Each group contained several commando units. The Einsatzgruppen gathered Jews town by town, marched them to huge pits dug earlier, stripped them, lined them up, and shot them with automatic weapons. The dead and dying would fall into the pits to be buried in mass graves. In the infamous Babi Yar massacre, near Kiev, 30,000-35,000 Jews were killed in two days. In addition to their operations in the Soviet Union, the Einsatzgruppen conducted mass murder in eastern Poland, Estonia, Lithuania and Latvia. It is estimated that by the end of 1942, the Einsatzgruppen had murdered more than 1.3 million Jews.

He had a wide variety of other research interests. Among these was a fascination with heterochromia, a condition in which the irises of an individual's eyes differ in coloration. Throughout his stay in Auschwitz, Mengele collected the eyes of his murdered victims, in part to furnish “research material” to colleague Karin Magnussen, a KWI researcher of eye pigmentation. He himself also conducted several experiments in an attempt to unlock the secret of artificially changing eye color. He also zealously documented in camp inmates the progression of the disease Noma, a type of gangrene which destroys the mucous membrane of the mouth and other tissues.

Along with several other Auschwitz doctors, Mengele transferred to Gross-Rosen concentration camp in Lower Silesia on 17 January 1945, taking with him two boxes of specimens and the records of his experiments at Auschwitz. Most of the camp medical records had already been destroyed by the SS[57][58] by the time the Red Army liberated Auschwitz on 27 January.[59] Mengele fled Gross-Rosen on 18 February, a week before the Soviets arrived there, and traveled westward to Žatec in Czechoslovakia, disguised as a Wehrmacht officer. There he temporarily entrusted his incriminating documents to a nurse with whom he had struck up a relationship.[57] He and his unit then hurried west to avoid being captured by the Soviets, but were taken prisoners of war by the Americans in June 1945. Although Mengele was initially registered under his own name, he was not identified as being on the major war criminal list due to the disorganization of the Allies regarding the distribution of wanted lists, and the fact that he did not have the usual SS blood group tattoo.[60] He was released at the end of July and obtained false papers under the name "Fritz Ullman", documents he later altered to read "Fritz Hollmann".[61]