“The Oranienburg concentration camp was established as one of the first concentration camps on March 21, 1933, overshadowed by the Day of Potsdam. After the “Night of the Long Knives,” the SA-run camp was taken over by the SS in July 1934 and dissolved a little later…

Initially SA-Regiment 208 (Standarte 208) established the Oranienburg concentration camp without notifying the responsible authorities in Berlin beforehand. The first inmates were 40 prisoners who were dragged to the small town 20 kilometers (12.4 miles) north of Berlin on the evening of March 21, 1933. The first concentration camp in Prussia was thus situated on the grounds of a former brewery on a main road in Oranienburg. From September 1933, subcamps existed at the Elisenau manor in Blumberg near Bernau and in Börnicke. (https://encyclopedia.ushmm.org/content/en/article/oranienburg-1)

“Seger managed to escape in December 1933, fleeing first to Czechoslovakia and later to the United States of America. His book on the terror in Oranienburg was one of the first books written about the conditions in a concentration camp from firsthand experience.” (Holocaust Encyclopaedia)

“Only a few days after the establishment of the camp, SA Standartenführer Werner Schulze-Wechsungen transferred control of the camp to the Potsdam district president. Henceforth the camp as well as the guards were paid from tax money. In total, the German tax payer paid 280,000 Reichsmark (RM) between August 1933 and July 1934 to sustain the camp. Internment in the camp was initiated not only by the police and party authorities but also by local administrative authorities. Only because of its location in the town, the camp proved to be a “transparent concentration camp.” The town of Oranienburg had the political prisoners perform communal work. The camp commander, SA-Sturmbannführer Werner Schäfer, compiled an apologetic “Anti-Brown Book” (Anti-Braunbuch), in which he characterized allegations about the Oranienburg concentration camp as “atrocious propaganda.”  Repeatedly he invited German and foreign journalists to tour the camp. A radio program “reported” from the concentration camp. The local press wrote extensively about the new institution. Also, movie theaters showed propagandistic
photos of the new concentration camp.

About 3,000 prisoners were deprived of their liberty in the Oranienburg concentration camp. The number of prisoners varied considerably. It rose rapidly until August 1933, from 97 to 911, but declined by the end of June 1934 to 271. The prisoners were mostly between the ages of 20 and 40, laborers, unemployed, from Berlin and from the area north of Berlin. Many were taken to Oranienburg after the dissolution of smaller Brandenburg concentration camps (including Alt Daber, Börnicke, Havelberg, and Perleberg) in June and July 1933. Prisoners from the concentration camps in Börgermoor, Lichtenburg, and Sonnenburg were interned at Oranienburg in September and October. Most of the inmates were members of the German Communist Party (KPD), the Social Democratic Party (SPD), and smaller left-wing organizations such as the Socialist Workers’ Party (SAP) and the German Communist Party Opposition (KPO). It is noteworthy that about 50 Jewish youths were also carried off to the camp from a home dedicated to advanced pedagogical ideas that was operated by the German Jewish Community Association (Deutsch-israelitischer  Gemeindebund) in Wolzig. They had been abducted because of “Communist activities”.” (Holocaust Encyclopaedia)