Between 1933 and 1945, Nazi Germany and its allies established more than 42,000 camps and other incarceration sites (including ghettos). The perpetrators used these sites for a range of purposes, including forced labor, detention of people thought to be enemies of the state, and mass murder.
In March 1933, the first concentration camp, Dachau, opened outside of Munich, Germany. It was used primarily for political prisoners and was the longest running camp in operation, until its liberation in April 1945.
There were more than 42,000 incarceration sites during the Holocaust. This estimate is based on continuing research of the perpetrators’ own records.
Not all facilities established were concentration camps, though they are often referred to that way. These sites varied in purpose and in the types of prisoners detained there.
From its rise to power in 1933, the Nazi regime built a series of incarceration sites to imprison and eliminate so-called "enemies of the state." Most prisoners in the early concentration camps were German Communists, Socialists, Social Democrats, Roma (Gypsies), Jehovah's Witnesses, homosexuals, and persons accused of "asocial" or socially deviant behavior. Some of these facilities were called “concentration camps” because those imprisoned there were physically “concentrated” in one location.
After Germany's annexation of Austria in March 1938, the Nazis arrested German and Austrian Jews and imprisoned them in the Dachau, Buchenwald, and Sachsenhausen concentration camps, all located in Germany. Following the violent Kristallnacht ("Night of Broken Glass") pogroms in November 1938, the Nazis conducted mass arrests of adult male Jews and incarcerated them in camps for brief periods.
Many people refer to all of the Nazi incarceration sites during the Holocaust as concentration camps. The term concentration camp is used very loosely to describe places of incarceration and murder under the Nazi regime, however, not all sites established by the Nazis were concentration camps. Nazi-established sites include:
Other types of incarceration sites numbered in the tens of thousands. These included but were not limited to early camps, euthanasia facilities, SS police and detention camps, and Germanization facilities.
Concentration camps are often inaccurately compared to a prison in modern society. But concentration camps, unlike prisons, were independent of any judicial review. Nazi concentration camps served three main purposes:
The First Concentration Camp
The major purpose of the earliest concentration camps during the 1930s was to kill or intimidate the leaders of political, social, and cultural movements that the Nazis perceived to be a threat to the survival of the regime. The first Nazi concentration camp was Dachau, established in March 1933, near Munich.
In most of the concentration camps, the Nazi SS either installed or had plans to install gas chambers to assist in their daily business of killing prisoners who were too weak or sick to work. Gas chambers were also to kill small targeted groups of individuals whom the Nazis wanted to eliminate (Polish resistance fighters, Soviet POWs, etc.). This was the purpose of the installation of gas chambers at Mauthausen, Sachsenhausen, Stutthof, Auschwitz I, Ravensbrück, Lublin/Majdanek, etc.
All concentration camps were structured in the same way. Each had an internal camp staff that consisted of five sections:
Following the German invasion of Poland in September 1939, the Nazis opened forced-labor camps where thousands of prisoners died from exhaustion, starvation, and exposure. SS units guarded the camps. During World War II, the Nazi camp system expanded rapidly. In some camps, Nazi doctors performed medical experiments on prisoners.
Following the June 1941 German invasion of the Soviet Union, the Nazis increased the number of prisoner-of-war (POW) camps. Some new camps were built at existing concentration camp complexes (such as Auschwitz) in occupied Poland. The camp at Lublin, later known as Majdanek, was established in the autumn of 1941 as a POW camp and became a concentration camp in 1943. Thousands of Soviet POWs were shot or gassed there.
Jews in Nazi-occupied lands often were first deported to transit camps such as Westerbork in the Netherlands, or Drancy in France, en route to the killing centers in occupied Poland. The transit camps were usually the last stop before deportation to a killing center.
To help carry out the "Final Solution" (the genocide or mass destruction of Jews), the Nazis established killing centers in German-occupied Poland, the country with the largest Jewish population. Killing centers were designed for efficient mass murder. The first one, which opened in December 1941, was Chelmno, where Jews and Roma were gassed in mobile gas vans. In 1942, the Nazis opened the Belzec, Sobibor, and Treblinka killing centers to systematically murder the Jews of the Generalgouvernement (the territory in the interior of German-occupied Poland).
Nazis constructed gas chambers (rooms that filled with poison gas to kill those inside) to increase killing efficiency and to make the process more impersonal for the perpetrators. At the Auschwitz camp complex, the Birkenau killing center had four gas chambers. During the height of deportations to the camp in 1943-44, an average of 6,000 Jews were gassed there each day.
Millions of people were imprisoned and abused in the various types of Nazi camps. Under SS management, the Germans and their collaborators murdered more than three million Jews in the killing centers alone. Only a small fraction of those imprisoned in Nazi camps survived.
Gutman, Yisrael and Michael Berenbaum, eds. Anatomy of the Auschwitz Death Camp. Bloomington: Indiana University Press, 1994.
The United States Holocaust Memorial Museum Encyclopedia of Camps and Ghettos, 1933-1945. Vol 1, Early Camps, Youth Camps, and Concentration Camps and Subcamps under the SS-Business Administration Main Office (WVHA), ed. Geoffrey Megargee. Bloomington: Indiana University Press in association with the United States Holocaust Memorial Museum, 2009.
Wachsmann, Nikolaus. KL: A History of the Nazi Concentration Camps. Farrar, Straus and Giroux, 2015.