Auschwitz-Birkenau ( ) was the largest of the German Nazi concentration and extermination camp complex. Located in German-occupied southern Poland, it took its name from the nearby town of Oświęcim (Auschwitz in German), situated about 50 kilometers west of Kraków and 286 kilometers from Warsaw. Following the German occupation of Poland in September 1939, Oświęcim was incorporated into Germany as part of the Katowice District (Regierungsbezirk Kattowitz), or unofficially East Upper Silesia (Ost-Oberschlesien), and renamed Auschwitz. There were also around 40 satellite camps, some of them tens of kilometers from the main camps, with prisoner populations ranging from several dozen to several thousand. Gutman, Yisrael. "Auschwitz—An Overview" in Gutman, Yisrael & Berenbaum, Michael. Anatomy of the Auschwitz Death Camp, Indiana University Press, 1994; this edition 1998, p. 17.

The camp commandant, Rudolf Höß (in English commonly Hoess or Höss), testifed at the Nuremberg Trials that 3 million people had died at Auschwitz during his stay as a commandant. Later he decreased his estimate to about 1.1 million. The death toll given by the Soviets and accepted by many was 4,000,000 people. This number was written on the plaques in the Auschwitz-Birkenau State Museum. The Museum revised this figure in 1990, and new calculations by Dr. Franciszek Piper now place the figure at 1.1 million about 90 percent of them were Jews from almost every country in Europe. Piper, Franciszek Piper. "The Number of Victims" in Gutman, Yisrael & Berenbaum, Michael. Anatomy of the Auschwitz Death Camp, Indiana University Press, 1994; this edition 1998, p. 62. Most deportees were killed in gas chambers using Zyklon B; other deaths were caused by systematic starvation, forced labor, lack of disease control, individual executions, and medical experiments.