The camp’s liberation was marked by the best and the worst of behavior by its victorious American liberators. Crazed by grief and anger at the appalling scenes on the day of the camp’s liberation, U.S. soldiers and camp inmates summarily executed some 520 of the camp’s German soldiers who had surrendered. After senior officers restored order, U.S. medical personnel began lifesaving measures for the most severely ill prisoners, and soldiers shared their rations and cigarettes with emaciated survivors.
In early 1937, the SS, using prisoner labor, began construction of a large complex of buildings on the grounds of the original camp. Prisoners were forced to do this work, starting with the destruction of the old munitions factory, under terrible conditions. The construction was officially completed in mid-August 1938 and the camp remained essentially unchanged until 1945. Dachau thus remained in operation for the entire period of the Third Reich.
In September 1939, the German army occupied the western half of Poland. German police soon forced tens of thousands of Polish Jews from their homes and into ghettoes, giving their confiscated properties to ethnic Germans (non-Jews outside Germany who identified as German), Germans from the Reich or Polish gentiles. Surrounded by high walls and barbed wire, the Jewish ghettoes in Poland functioned like captive city-states, governed by Jewish Councils. In addition to widespread unemployment, poverty and hunger, overpopulation made the ghettoes breeding grounds for disease such as typhus.
According to testimony given at the Nuremberg IMT, approximately 150 Dachau inmates were forced to participate in medical experiments conducted by Dr. Sigmund Rascher for the German Air Force, and about half of them died as a result. The subjects for these experiments were allegedly German "professional criminals" and Soviet POWs who were Communist Commissars, sentenced to be executed on the orders of Adolf Hitler. One Jew, who had been condemned to death for breaking the law against race mixing, was used in these experiments.
In 1944, Josiah DuBois, Jr. wrote a memorandum to then-Secretary of the Treasury Henry Morgenthau, Jr. entitled “Report to the Secretary on the Acquiescence of This Government in the Murder of the Jews”, which condemned the bureaucratic interference of U.S. State Department policies in obstructing the evacuation of Holocaust Refugees from Romania and Occupied France. The Report would spur the Roosevelt administration to create the War Refugee Board later that year.
^ Nazi Science – The Dachau Hypothermia Experiments. Robert L. Berger, N Engl J Med 1990; 322:1435–1440 May 17, 1990 DOI: 10.1056/NEJM199005173222006. quote: "On analysis, the Dachau hypothermia study has all the ingredients of a scientific fraud, and rejection of the data on purely scientific grounds is inevitable. They cannot advance science or save human lives." ... "Future citations are inappropriate on scientific grounds."
The workers who constructed the original buildings were housed in camps near Fallingbostel and Bergen, the latter being the so-called Bergen-Belsen Army Construction Camp. Once the military complex was completed in 1938/39, the workers' camp fell into disuse. However, after the German invasion of Poland in September 1939, the Wehrmacht began using the huts as a prisoner of war (POW) camp.