In June 1940, the nazis set up a concentration camp for Polish opponents to the Nazi regime on the outskirts of the Polish border town Oświęcim, a few kilometres west of the city of Kraków. The name Oświęcim was changed to the German name Auschwitz and from 1941 to 1942 grew into the biggest extermination camp for Jews from all over Europe. In September 1939, the nazis had incorporated West Poland into the German Reich. In merely a few weeks the nazis tried to 'germanise' (by means of ethnic cleansing) the Kattowice district, in which Oświęcim was located. Jews from the entire district were forced to move to the old town centre of Auschwitz, living in crowded conditions along the narrow alleys, separated from the rest of the population, and under the strict supervision of the German guards. At the beginning of 1940, Himmler set his eyes on Auschwitz. On 14 June 1940, Auschwitz began to operate as a quarantine and transit camp. The first Polish prisoners were deployed mainly to make the old and partly walled Polish army camp suitable as a concentration camp.