Below are figures for the number of Jews murdered in each country that came under German domination. They are estimates, as are all figures relating to Holocaust victims. The numbers given here for Czechoslovakia, Hungary and Romania are based on their territorial borders before the 1938 Munich agreement. The total number of six million Jews murdered during the Holocaust, which emerged from the Nuremberg trials, is also an estimate. Numbers have ranged between five and seven million killed.

Entering conquered Soviet territories alongside the Wehrmacht (the German armed forces) were 3,000 men of the Einsatzgruppen (“Deployment Groups”), special mobile killing units. Their task was to murder Jews, Soviet commissars, and Roma in the areas conquered by the army. Alone or with the help of local police, native anti-Semitic populations, and accompanying Axis troops, the Einsatzgruppen would enter a town, round up their victims, herd them to the outskirts of the town, and shoot them. They killed Jews in family units. Just outside Kiev, Ukraine, in the ravine of Babi Yar, an Einsatzgruppe killed 33,771 Jews on September 28–29, 1941. In the Rumbula Forest outside the ghetto in Riga, Latvia, 25,000–28,000 Jews were shot on November 30 and December 8–9. Beginning in the summer of 1941, Einsatzgruppen murdered more than 70,000 Jews at Ponary, outside Vilna (now Vilnius) in Lithuania. They slaughtered 9,000 Jews, half of them children, at the Ninth Fort, adjacent to Kovno (now Kaunas), Lithuania, on October 28.

In 1939, shortly after the war began, the Germans initiated the T4 Program—framed euphemistically as a “euthanasia” program—for the murder of intellectually or physically disabled and emotionally disturbed Germans who by their very existence violated the Nazi ideal of Aryan supremacy. They were termed “life unworthy of life.” An economic justification was also employed as these Germans were considered “useless eaters.” The Nazis pioneered the use of gas chambers and mass crematoria under this program. The murder of the disabled was the training ground for key personnel who were to later staff the death camps of Aktion Reinhard. The German public protested these murders. The Roman Catholic bishop of Münster, Clemens August, Graf von Galen, preached against them, and the T4 program was formally halted. Nonetheless, the murder and sterilization of these German “Aryans” continued secretly throughout the war.

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]
Dan Stone, a specialist in the historiography of the Holocaust, lists ethnic Poles, Ukrainians, Soviet prisoners of war, Jehovah's Witnesses, black Germans, and homosexuals as among the groups persecuted by the Nazis; he writes that the occupation of eastern Europe can also be viewed as genocidal. But the German attitude toward the Jews was different in kind, he argues. The Nazis regarded the Jews not as racially inferior, deviant, or enemy nationals, as they did other groups, but as a "Gegenrasse: a 'counter-race', that is to say, not really human at all". The Holocaust, for Stone, is therefore defined as the genocide of the Jews, although he argues that it cannot be "properly historically situated without understanding the 'Nazi empire' with its grandiose demographic plans".[d] Donald Niewyk and Francis Nicosia, in The Columbia Guide to the Holocaust (2000), favour a definition that focuses on the Jews, Roma, and Aktion T4 victims: "The Holocaust—that is, Nazi genocide—was the systematic, state-sponsored murder of entire groups determined by heredity. This applied to Jews, Gypsies, and the handicapped."[33]
The word “Holocaust,” from the Greek words “holos” (whole) and “kaustos” (burned), was historically used to describe a sacrificial offering burned on an altar. Since 1945, the word has taken on a new and horrible meaning: the mass murder of some 6 million European Jews (as well as millions of others, including Gypsies and homosexuals) by the German Nazi regime during the Second World War. To the anti-Semitic Nazi leader Adolf Hitler, Jews were an inferior race, an alien threat to German racial purity and community. After years of Nazi rule in Germany, during which Jews were consistently persecuted, Hitler’s “final solution”–now known as the Holocaust–came to fruition under the cover of world war, with mass killing centers constructed in the concentration camps of occupied Poland.

Bergen-Belsen [ˈbɛʁɡn̩.bɛlsn̩], or Belsen, was a Nazi concentration camp in what is today Lower Saxony in northern Germany, southwest of the town of Bergen near Celle. Originally established as a prisoner of war camp,[1] in 1943, parts of it became a concentration camp. Initially this was an "exchange camp", where Jewish hostages were held with the intention of exchanging them for German prisoners of war held overseas.[2] The camp was later expanded to accommodate Jews from other concentration camps.