Blitzkrieg's widest influence was within the Western Allied leadership of the war, some of whom drew inspiration from the Wehrmacht's approach. United States General George S. Patton emphasized fast pursuit, the use of an armored spearhead to effect a breakthrough, then cut off and disrupt enemy forces prior to their flight. In his comments of the time, he credited Guderian and Rommel's work, notably Infantry Attacks, for this insight. He also put into practice the idea attributed to cavalry leader Nathan Bedford Forrest, "Get there fastest with the mostest." (Get there fastest, with the most forces).
Of the 430,000 sent to the first death camp at Bełżec in Poland, there were only two survivors. 700,000 were killed at Treblinka in just five months. In July, Himmler ordered that all Jews in key areas of Poland, except for those needed for essential labour, were to be killed by the end of the year. Most were. Despite Allied intelligence receiving detailed reports of the mass murders in Europe, the public reaction in Britain was largely a mixture of apathy and disbelief.
The first prisoners at Auschwitz included German prisoners transferred from Sachsenhausen concentration camp in Germany, where they had been incarcerated as repeat criminal offenders, and Polish political prisoners from Lodz via Dachau concentration camp and from Tarnow in Krakow District of the Generalgouvernement (that part of German-occupied Poland not annexed to Nazi Germany, linked administratively to German East Prussia, or incorporated into the German-occupied Soviet Union).
Before beginning Jewish exterminations, though, the Nazi’s used the Soviet POWs at the Auschwitz camp in trials of the poison gas Zyklon-B, produced by the German company “Degesch” (Deutsche Gesellschaft zur Schädlingsbekämpfung), which was marked as the best way to kill many people at once. The POWs were gassed in underground cells in Block 11, the so called “Death Block,” and following these trials, one gas chamber was setup just outside the main camp and two temporary gas chambers were opened at Birkenau.