On the night of January 30-31, 1945, as the Soviet Red Army approached from the Eastern Front of World War II, some 819 political prisoners from many European countries were executed at the Sonnenburg concentration camp on the Polish.

On the night of January 30-31, 1945, as the Soviet Red Army approached from the Eastern Front of World War II, some 819 political prisoners from many European countries were executed at the Sonnenburg (Sonnenburg) concentration camp. A group of SS detachments and Gestapo from Frankfurt, along the Oder River on the Polish border, carried out the massacre in the courtyard of the concentration camp. At about 10:00 p.m., the guards divided the prisoners into groups of ten and took them into the concentration camp courtyard. The Gestapo lined up about 800 or more prisoners against the wall and shot them to death. Survivors were killed with machine guns aimed at the back of the head. After the massacre, fire was set on some of the corpses, and when Soviet soldiers entered the Sonnenburg camp on February 2, their bodies were still lying in the courtyard. Among the corpses at the execution site, four survived.

　The Sonnenburg concentration camp, located in Suhons on the Polish border about 95 km east of Berlin, was officially closed on April 23, 1934, but was still used in practice; since the beginning of World War II in September 1939, concentration camps or punishment camps had been used as anti-German concentration camps and labor camps for anti-German citizens of the occupied territories until 1945. The concentration camps contained political prisoners, all of whom opposed the Nazi Third Reich, and at the time the Gestapo was ordered to withdraw the concentration camps on January 30, 1945, the Soviet Red Army was only 35 km from Sonnenburg. The concentration camp was ruled by torture, and the east basement and west wing of the camp were separated into cells called torture chambers. Prisoners were exhausted, demoralized, and terrified, and many chose to die and commit suicide.

　Sonnenburg (now Sunnsk) was the first concentration camp of the Nazi Third Reich, and on April 4, 1933, the first transfer of prisoners arrived at Sonnenburg; the political opponents of Adolf Hitler, who had just come to power in early 1933, were at the heart of the prisoners and immediately began a purge. Underground storage rooms in the capital Berlin were used as temporary prisons, but they were already overcrowded. Sonnenburg was located about 95 km from Berlin and was connected to Berlin by rail. Poor working conditions, poor nutrition, torture, and lack of medical care led to the spread of deadly epidemics among the prisoners. The prisoners in the concentration camps were all citizens who were averse to National Socialism: communists, social democrats, pacifists, Jews, Catholics, Protestants, workers, and political professionals.