On January 20, 1942, Reinhard Heydrich convened the Wannsee Conference at a lakeside villa in Berlin to organize the “final solution to the Jewish question.” Around the table were 15 men representing government agencies necessary to implement so bold and sweeping a policy. The language of the meeting was clear, but the meeting notes were circumspect:
In the summer of 1942, Germany launched another offensive in the southern USSR against Stalingrad and the Caucasus, the Soviets again lost tremendous amounts of territory, only to counter-attack once more during winter. German gains were ultimately limited by Hitler diverting forces from the attack on Stalingrad and driving towards the Caucasus oilfields simultaneously. The Wehrmacht became overstretched, although winning operationally, it could not inflict a decisive defeat as the durability of the Soviet Union's manpower, resources, industrial base and aid from the Western Allies began to take effect.[95]

In July 1943 the Wehrmacht conducted Operation Zitadelle (Citadel) against a salient at Kursk that was heavily defended by Soviet troops.[97][98] Soviet defensive tactics were by now hugely improved, particularly in the use of artillery and air support.[98][99] By April 1943, the Stavka had learned of German intentions through intelligence supplied by front line reconnaissance and Ultra intercepts.[100] In the following months, the Red Army constructed deep defensive belts along the paths of the planned German attack.[101] The Soviets made a concerted effort to disguise their knowledge of German plans and the extent of their own defensive preparations, and the German commanders still hoped to achieve operational surprise when the attack commenced.[102]
Following the camp's liberation, the Soviet government issued a statement, on 8 May 1945, that four million people had been killed on the site, a figure based on the capacity of the crematoria and later regarded as too high.[184] Höss told prosecutors at Nuremberg that at least 2,500,000 people had been murdered in Auschwitz by gassing and burning, and that another 500,000 had died of starvation and disease.[185] He testified that the figure of over two million had come from Eichmann.[186][d] In his memoirs, written in custody, he wrote that he regarded this figure as "far too high. Even Auschwitz had limits to its destructive possibilities."[188] Raul Hilberg's 1961 work, The Destruction of the European Jews, estimated that up to 1,000,000 Jews had died in Auschwitz.[189]
Some ghettos were initially open, which meant that Jews could leave the area during the daytime but had to be back by a curfew. Later, all ghettos became closed, meaning that Jews were not allowed to leave under any circumstances. Major ghettos were located in the cities of Polish cities of Bialystok, Lodz, and Warsaw. Other ghettos were found in present-day Minsk, Belarus; Riga, Latvia; and Vilna, Lithuania. The largest ghetto was in Warsaw. At its peak in March 1941, some 445,000 were crammed into an area just 1.3 square miles in size.
By July 1944, Germany was losing the war; the SS began closing down the easternmost concentration camps and deporting the remaining prisoners westward. Many were killed in Auschwitz and the Gross-Rosen concentration camp. Schindler convinced SS-Hauptsturmführer Amon Göth, commandant of the nearby Kraków-Płaszów concentration camp, to allow him to move his factory to Brněnec in the Protectorate of Bohemia and Moravia, thus sparing his workers from almost certain death in the gas chambers. Using names provided by Jewish Ghetto Police officer Marcel Goldberg, Göth's secretary Mietek Pemper compiled and typed the list of 1,200 Jews who travelled to Brünnlitz in October 1944. Schindler continued to bribe SS officials to prevent the execution of his workers until the end of World War II in Europe in May 1945, by which time he had spent his entire fortune on bribes and black market purchases of supplies for his workers.