^ Hitler stated: "Today our left-wing politicians in particular are constantly insisting that their craven-hearted and obsequious foreign policy necessarily results from the disarmament of Germany, whereas the truth is that this is the policy of traitors […] But the politicians of the Right deserve exactly the same reproach. It was through their miserable cowardice that those ruffians of Jews who came into power in 1918 were able to rob the nation of its arms." Adolf Hitler. Mein Kampf. Bottom of the Hill Publishing, 2010. p. 287.
The gas chambers worked to their fullest capacity from April to July 1944, during the massacre of Hungary's Jews. Hungary was an ally of Germany during the war, but it had resisted turning over its Jews until Germany invaded that March. A rail spur leading to crematoria II and III in Auschwitz II was completed that May, and a new ramp was built between sectors BI and BII to deliver the victims closer to the gas chambers. On 29 April the first 1,800 Hungarian Jews arrived at the camp; from 14 May until early July 1944, 437,000 Hungarian Jews, half the pre-war population, were deported to Auschwitz, at a rate of 12,000 a day for a considerable part of that period. The crematoria had to be overhauled. Crematoria II and III were given new elevators leading from the stoves to the gas chambers, new grates were fitted, and several of the dressing rooms and gas chambers were painted. Cremation pits were dug behind crematorium V. The last mass transports to arrive in Auschwitz were 60,000–70,000 Jews from the Łódź Ghetto, some 2,000 from Theresienstadt, and 8,000 from Slovakia. The last selection took place on 30 October 1944. Crematorium IV was demolished after the Sonderkommando revolt on 7 October 1944. The SS blew up crematorium V on 14 January 1945, and crematoria II and III on 20 January.
Heinrich Himmler's Schutzstaffel (SS) took full control of the police and the concentration camps throughout Germany in 1934–35. Himmler expanded the role of the camps to hold so-called "racially undesirable elements", such as Jews, Gypsies/Romanis/Sintis, Serbs, Poles, disabled people, and criminals. The number of people in the camps, which had fallen to 7,500, grew again to 21,000 by the start of World War II and peaked at 715,000 in January 1945.