The Schutzstaffel (SS) was founded in 1925 to provide party security. It was Hitler’s bodyguard and protected NSDAP events. Initially it was subordinate to the much larger Sturmabteilung (SA), a paramilitary organisation within the NSDAP. When Heinrich Himmler, an agriculturalist by training, took charge of the SS in 1929, it had only a few hundred members. Under his leadership, the SS rose to become one of the most powerful institutions within the Nazi state.

With Hitler appointed as Reich chancellor in 1933, the SS began its persecution of the political opponents of National Socialism. Its instruments of terror were the SS concentration camps, outside the ordinary reach of the law. In the years that followed, ever-larger sections of the population were sent to the camps: homosexuals, people described as “antisocial” or “career criminals” and people persecuted because of their race – Jews, Sinti and Roma.

By 1936, Himmler gained control over the entire police force. The intention was for it to merge with the SS into a Nazi “State Security Corps”, oriented not by law and justice but by the “will of the Führer” and of the “national community”, or Volksgemeinschaft. The SS, for Himmler, was a brotherhood with strict acceptance criteria, the nucleus of the racist new order in Europe.

When the war began, the SS and police provided security in the areas occupied by the Wehrmacht. Particularly in Eastern Europe, which was to be cleared for settlement by Germans in the future, SS units committed atrocities against the civilian population. The genocides of European Jews, Sinti and Roma were to a significant extent planned and executed by the SS.

The General Staff of the Reichsführer-SS coordinated the multifarious activities of the SS, which was active not only in police, secret service and military matters, but also in the economy, science and culture. Its office was located at Prinz-Albrecht-Straße 8.

With their seizure of power in 1933, the National Socialists gained control over the police, through which they exercised state violence. In Prussia, the largest state of the German Reich, the new Minister President Hermann Göring developed the Political Police into a special authority with extensive executive power. The “GEheime STAatsPOlizei”, the Gestapo, founded in 1933, was taken out of general police administration and physically separated from it too. The Gestapo offices were relocated to the former school of arts and crafts at Prinz-Albrecht-Straße 8. The new authority was intended to combat all “political movements dangerous to the state”. With the powers of the Reichstag Fire Decree of 28 February 1933, the Gestapo could act independently and take people into unlimited “protective custody”.

In Munich, Heinrich Himmler was appointed head of the newly founded Bavarian Political Police. As Reichsführer-SS, he was in charge of the Dachau concentration camp in which this body interned its prisoners. Starting from Bavaria, Himmler gradually took control over Political Police forces in the other states, finally taking charge in Prussia in April 1934 as Inspector of the Gestapo.

Once appointed Chief of the German Police, Himmler began to reorganise the police apparatus from 1936 onwards. The Gestapo and investigative police were combined under a Central Security Police Office; the uniformed police under a Central Order Police Office. Now, the Gestapo’s sights were not only on political enemies such as communists and social democrats. All groups declared “enemies of the people” were persecuted. This particularly included the Jewish population.

In the early years, the staff of the Gestapo were largely detectives trained under the Weimar Republic. They were aided in their work by other authorities and party offices, though also by denunciations from private citizens.

The Sicherheitsdienst (SD) of the SS, an intelligence agency founded on Himmler's initiative in 1931, monitored members of the NSDAP and its enemies. The head of the SD was Reinhard Heydrich, a former naval officer. In its early days the SD only employed a few full-time employees and competed with other intelligence services of the NSDAP.

After the seizure of power by the Nazis, the SD rose to become the only intelligence agency of the NSDAP after 1934. It moved into offices in the Prinz-Albrecht-Palais, Wilhelmstraße 102. The SD was systematically developed by Heydrich. As a domestic security agency, the SD claimed the task of monitoring all areas of public life. Regular situation reports informed the party and state leadership of the mood among the population. Less important was the foreign secret service of the SD, which competed with the Wehrmacht’s intelligence service in espionage and counterintelligence.

The SD shared its knowledge of political and ideological enemies of National Socialism with the Gestapo, which retained executive authority. This separation between intelligence and police work broke down after the start of the war. In the Einsatzgruppen (“task forces”) deployed from 1939 in Poland and 1941 in the Soviet Union, SD employees and Gestapo officers alike organised mass shootings of Jews, prisoners of war, functionaries of the communist party, Sinti and Roma.

The leadership of the SD was largely occupied by young academics from various disciplines. They considered themselves the ideological elite of National Socialism. In total, the SD had around 6,000 employees, supported by an estimated 30,000 informers from all classes of society.

After the start of the war in 1939, Himmler once again reorganised the police. The Security Police – Gestapo and investigative police – were combined with the Sicherheitsdienst of the SS under the Reich Security Main Office (RSHA). The RSHA thus melded a state institution – the police – with a party organ. This created an authority with extensive power. It helped to secure National Socialist hegemony and realised its racist ideas through violence. The head of the RSHA up to his assassination in 1942 was Reinhard Heydrich, followed by Ernst Kaltenbrunner, an Austrian lawyer, from 1943.

Within the RSHA, headquartered at Prinz-Albrecht-Straße 8, the Gestapo, investigative police and SD retained independent offices. The training of leaders, however, took place in a shared training facility. With its subordinate offices, the RSHA was represented across the entire German Reich and occupied territories in Europe. Over the course of the war, offices and departments of the headquarters continued to be hived off to other locations within and outside of Berlin.

Departments of the RSHA were responsible for the deportation and murder of European Jews, Sinti and Roma, for countering any form of resistance, for placing people in concentration camps and guarding millions of forced workers. At the high-water-point of its power in 1944, the RSHA and its external offices could count on 50,000 employees. More than 31,000 of these were in the Gestapo, with almost 13,000 in the investigative police. The RSHA headquarters employed about 3,500 people.

In August 1933, an in-house prison was established in the basement of the Gestapo offices at Prinz-Albrecht-Straße 8. Its purpose was to hold prisoners the Gestapo was particularly interested in interrogating. These included numerous members of the German resistance, alongside foreign opponents of the Nazi regime.

A large number of the almost exclusively male internees were political prisoners. With 38 individual cells and one communal cell, the in-house prison remained small, even after its extension in 1936. Many prisoners were thus actually held at different prisons around Berlin and were only brought to Prinz-Albrecht-Straße 8 for interrogation.

The interrogations could last hours, days, even weeks and months. Prisoners were tortured during interrogation. Some of them committed suicide while interned. But long-term imprisonment was more the exception than the rule. For most prisoners, the in-house prison was just one stop on a longer route through various institutions and concentration camps.

At the beginning, the Gestapo imprisoned members of the soon-to-be-outlawed left-wing parties (KPD, SAP, SPD) and the resistance groups they spawned. During the Second World War, numerous members of the “Red Chapel” resistance group were held, as were representatives of the various civil and military groups involved in the attempted assassination of the Führer on 20 July 1944. But there were also many other kinds of people detained in the in-house prison – those who, for example, resisted the Nazi regime because of their Christian faith or as a matter of conscience.

Documentation allowing us to know the exact number of people held in the prison from 1933 to 1945 is not available. Our estimate puts the number at several thousand.