The Nazis and their collaborators killed children for these ideological reasons and in retaliation for real or alleged partisan attacks.

[2] Early killings were encouraged by the Nazis in Aktion T4, where children with disabilities were gassed using carbon monoxide, starved to death, given phenol injections to the heart, or hanged.

Although the basis for these decisions was "race-scientific," often blond hair, blue eyes, or fair skin was sufficient to merit the "opportunity" to be "Germanized."

[7] Author Robert Jay Lifton describes Mengele as sadistic, lacking empathy, and extremely anti-Semitic, claiming that he believed that the Jews should be eliminated entirely as an inferior and dangerous race.

He operated on children, partly to find genetic weaknesses in the makeup of Jewish or Romani people in order to provide scientific evidence for the ideas of the Nazi party.

[14] Miklós Nyiszli, a prisoner at Auschwitz, recalled one occasion where Mengele personally killed fourteen twins in one night through a chloroform injection to the heart.

[21] During the existence of the Independent State of Croatia during World War II, the Croatian Ustaše established numerous concentration camps like those in Jasenovac,[22] Đakovo,[23] and Jastrebarsko[24] in which many Serbian, Jewish, and Romani children died as inmates.

When a typhus epidemic broke out, Najžer ordered the transfer of the infected children to an improvised hospital, only serving to increase the number of deaths.

In Teslic glasshouse and the newly built barracks, which were named "Karantena", a general concentration camp for men, women, and children had been established.

Lazar Margulješ testified about conditions at the concentration camp:[30] I've noticed that the food parcels sent by Red Cross have never been given to the imprisoned children.

My duty as a medic was to research these small prisoners, therefore I often visited these places: Sokolana building, where the children laid on bare concrete or, if they had little luck, on a little straw.

The so-called hospital, in a small school in Old Sisak, had no beds so the children were lying on the floor with a little distracted and contaminated straw matted with blood and excrement and covered with swarms of flies.Jana Koh, former secretary of Croatian Red Cross stated following about the conditions in the Camp: The barracks were connected by the corridors guarded by the Ustashas.

Coroner David Egić officially recorded that out of 6,693 children, 1,152 died in the Camp, while teacher Ante Dumbović later claimed that the number was 1,630.

It brought about 10,000 refugee Jewish children to safety in Great Britain from Nazi Germany and German-occupied territories, although their families did not come with them.

[38] In the United States, some individuals attempted to help, and efforts around the country allowed the rescue of 1,000 Jewish children from Nazis.

[39] Gilbert and Eleanor Kraus were a couple who brought 50 Jewish children to the United States to save them from Nazis in 1939 before the war started.

In 1939, the Wagner-Rogers Bill was proposed, which was to admit 20,000 unaccompanied Jewish child refugees under the age of 14 into the United States.

Almost the entire Protestant population of Le Chambon-sur-Lignon, as well as many Catholic priests, nuns, and laymen, hid Jewish children in the town from 1942 to 1944.

[43] After the surrender of Nazi Germany, which ended World War II, refugees and displaced persons searched throughout Europe for missing children.

Many surviving Jewish children fled eastern Europe as part of the mass exodus (Brihah) to the western zones of occupied Germany en route to the Yishuv.

Youth Aliyah continued its activities after the war by helping child survivors to move to Palestine, which soon became the state of Israel in 1948.

These exemptions applied to Jewish children of mixed marriage, those with fathers who served in World War I, and those with foreign citizenship.

Additionally, teachers forbade Jewish students from participating in school activities and incorporated elements of the Nazi ideology in their classrooms, such as the use of anti-Semitic terms in class.

[47] Eventually many German Jews enrolled their children in Jewish schools in order to prevent persecution in the classroom.

[50] German forces established ghettos early in the war in many Polish towns and cities such as Warsaw and Łódź.

The German authorities were indifferent to this mass death because they considered most of the younger ghetto children to be unproductive and hence "useless eaters".

Children began to see their relatives in a different light because each family member dealt with various hardships in the transit camps.

Childcare workers taught children about the ideas of Zionism and the spirit of democracy; they additionally encouraged an affectionate atmosphere.

Other notable cases include the children held in the Majdanek concentration camp, some of whom were orphaned because their parents were killed in anti-partisan operations.

[56] Witness children typically expressed defiance to the Nazi regime's attempts to make them act against their beliefs.