Following the failure of operation Barbarossa and the Soviet advance into Poland the SS in charge of Auschwitz decided to evacuate the camp sometime in 1945 and marched its inhabitants towards Germany. Known as the "death marches” many inmates perished on this journey but those lucky and strong enough to survive were moved by train to other camps. Some, however, were able to escape during this process due to the chaos ensuing towards the end of the war. If you are interested in the story of one man that did survive the evacuation of Auschwitz I recommend the book the Tatooist of Auschwitz.