Also in 1936, a new camp called Sachsenhausen was built to replace the former "wild camp" that had been set up in an abandoned brewery in Oranienburg in 1933. The camp in the old brewery was the place where the famous "Arbeit Macht Frei" sign was first erected. When the new Dachau gate house was finished in June 1936, this slogan was put on the iron gate. The words mean "work will set you free." According to Rudolf Hoess, who was on the Dachau staff in 1936, the slogan meant that work sets one free in the spiritual sense, not literally.
The Third Reich first used concentration camps as places of unlawful incarceration of political opponents and other "enemies of the state". Large numbers of Jews were not sent there until after Kristallnacht in November 1938. Although death rates were high, the camps were not designed as killing centers. After war broke out in 1939, new camps were established, some outside Germany in occupied Europe. In January 1945, the SS reports had over 700,000 prisoners in their control, of which close to half had died by the end of May 1945 according to most historians. Most wartime prisoners of the camps were not Germans but belonged to countries under German occupation.
The government defined a Jewish person as someone with three or four Jewish grandparents, not someone who had religious convictions. This meant that people who had never practiced, or hadn’t practiced Judaism in many years, or even converted to Christianity were subjected to persecution. Although anti-semitism was pervasive in 1930s Germany, these restrictions frequently extended to any person the Nazis considered to be “non-Aryan”.
Throughout the 1930s, the legal, economic, and social rights of Jews were steadily restricted. On 1 April 1933, there was a boycott of Jewish businesses. On 7 April 1933, the Law for the Restoration of the Professional Civil Service was passed, which excluded Jews and other "non-Aryans" from the civil service. Jews were disbarred from practising law, being editors or proprietors of newspapers, joining the Journalists' Association, or owning farms. In Silesia, in March 1933, a group of men entered the courthouse and beat up Jewish lawyers; Friedländer writes that, in Dresden, Jewish lawyers and judges were dragged out of courtrooms during trials. Jewish students were restricted by quotas from attending schools and universities. Jewish businesses were targeted for closure or "Aryanization", the forcible sale to Germans; of the approximately 50,000 Jewish-owned businesses in Germany in 1933, about 7,000 were still Jewish-owned in April 1939. Works by Jewish composers, authors, and artists were excluded from publications, performances, and exhibitions. Jewish doctors were dismissed or urged to resign. The Deutsches Ärzteblatt (a medical journal) reported on 6 April 1933: "Germans are to be treated by Germans only."
A letter from Dr. Sigmund Rascher to Heinrich Himmler, the head of all the concentration camps, which makes a reference to a facility like the one at Hartheim which the Nazis were planning to build at Dachau, is the best proof that the fake shower room in Baracke X was actually a gas chamber. A copy of this letter was displayed in the gas chamber building in May 2001, but it was later moved to the Dachau Museum.
The camp was liberated on April 15, 1945, by the British 11th Armoured Division. The soldiers discovered approximately 60,000 prisoners inside, most of them half-starved and seriously ill, and another 13,000 corpses, including those of Anne and Margot Frank, lying around the camp unburied. The horrors of the camp, documented on film and in pictures, made the name "Belsen" emblematic of Nazi crimes in general for public opinion in many countries in the immediate post-1945 period. Today, there is a memorial with an exhibition hall at the site.