The first prisoners arrived in Dachau on March 22, 1933, two days after the acting Munich Chief of Police and Reichsführer SS Heinrich Himmler announced the camp’s creation.
During the first year, the camp held about 4,800 prisoners and by 1937 the number had risen to 13,260. Initially the internees consisted primarily of German Communists, Social Democrats, and other political opponents of the Nazi regime. Over time, other groups were also interned at Dachau such as Jehovah’s Witnesses, Roma (Gypsies), and homosexuals, as well as “asocials” and repeat criminals. During the early years relatively few Jews were interned in Dachau and usually because they belonged to one of the above groups or had completed prison sentences after being convicted for violating the Nuremberg Laws of 1935.
The first commandant of Dachau was SS official Hilmar Wäckerle. He was replaced in June 1933 after being charged with murder in the death of a prisoner.
In Dachau, as in other Nazi camps, German physicians performed medical experiments on prisoners, including high-altitude experiments using a decompression chamber, malaria and tuberculosis experiments, hypothermia experiments, and experiments testing new medications. Prisoners were also forced to test methods of making seawater potable and of halting excessive bleeding. Hundreds of prisoners died or were permanently crippled as a result of these experiments.
On 29 April 1945, the camp was liberated by the Seventh Army of the United States armed forces.
Over its twelve years as a concentration camp, the Dachau administration recorded the intake of 206,206 prisoners and 31,951 deaths.