On March 17, 1938, German units occupy the military headquarters at the Brucker Porte, and take over the camp in Kaisersteinbruch, together with barrack buildings. The area is then located in the Wehrmachtsbezirk XVII, which is responsible for the area of Vienna, Lower Austria and the Nordburgenland and is known as Gau Niederdonau. In the future, the regime plans to declare the site Kaisersteinbruch and some neighboring municipalities to the military restricted area, to resettle the resident population there and to expand and expand the military training place. According to an inventory of the Armed Forces Command (OKW), the camp in Kaisersteinbruch from 1938 to 1939 is used as a transit camp under the name DULAG J.
In Kaisersteinbruch, from September 1939 the STALAG XVII A was built, which is one of the first military camps in the Ostmark and also one of the first internment camps of the entire Reichsgebiet. The camp was then located on the eastern edge of the relocated municipality and consists of camps I and II. While the camp I consists of 41 bricked and four smaller barracks dating back to the last century, the 31 wooden huts built in Camp II, together with eight smaller buildings from the time of the Third Reich, are built. In January 1941, the camp reached a maximum capacity of 73,583 soldiers, 970 officers and 220 civilians after a brief period. In the years thereafter, the number of occupants is between 25,500 and 53,000. In February 1945, a total of 26,470 prisoners were registered through the review report of the IRCR.
The majority of the prisoners are French prisoners of war during the entire inventory, with Yugoslavs and Serbs from the summer of 1941, the Russians from December as well as the second-strongest group in the autumn of 1943. Further represented nationalities are Americans, Belgians, Dutch, English, Greeks, Poles and Czechs. The main share of French prisoners of war at that time meant that the French, through an autonomous self-administration, had a dominant influence on camp life by cooperating in various workshops and typing rooms. In the camp I, the British even form a subdivision separated from the rest by barbed wire. The camp I is evacuated by the Russian prisoners of war on April 18, 1942, after a pandemic spread of diseases, by the entire prisoners of war of other nations, which resulted in the so-called „Russian camp“. Together with the Slovakian, Romanian, and Bulgarian prisoners of war of the former allies, the Russians took the lowest position of the camp hierarchy in the last two years of the war, with regard to the „racial political“ affiliation with the Slavic peoples.
Wth the successive end of the war in 1945, in march the Red Army advanced from the east, as in all camps of the XVIIth militry district, the order to evacuate the inmates in the western direction between the end of March and the beginning of April, in order to transfer them to a prison camp that was still difficult to reach for the Soviet troops. The soldiers left behind in Kaisersteinbruch remain for some time after the liberation and before their repatriation in the camp, which in the following period is additionally populated by the accommodation of „Displaced Persons“ (DP’s). From 1945, the village Kaisersteinbruch is located in the Russian occupation zone, about 4,500 people of Russian origin live in the camp. Before the occupation of the occupying soldiers and their families, the former STALAG XVII A serves as camp No. 306, where „state criminals“ are interned, who are sent to Leninabad in Central Asia and Szeged at the beginning of May 1946.