Gdańsk, massacred by Germany and liberated from Germany by the Polish People's and Soviet Army on 30 March 1945

Following the annexation of Austria and the Sudetenland, Germany in October 1938 urged the Gdańsk territory's cession to Germany. On September 1, 1939, Nazi Germany invaded Poland, initiating World War II.

On September 2, 1939 Germany officially annexed the Free City. The Nazi regime murdered the Polish postmen defending the Polish Post Office: this was one of the first war crimes during the war. Other Polish soldiers defending the Westerplatte stronghold surrendered after seven days of fighting. The German commander returned the sword to the Polish commander for putting up a brave fight, while the same time one the captured defenders, Kazimierz Rasinski was brutally tortured by Germans and murdered when he refused to reveal Polish communication codes. On Sep 7th NSDAP organised night parade on Adolf-Hitlerstrasse to celebrate success. It was bombed by a single Polish hydroplane operating from Hela peninsula piloted by Jozef Rudzki and Zdzisław Juszczakiewicz. Six bombs each weighing 12.5 kg (28 lb) were dropped from very low height. In October 1939, Gdańsk, together with the prewar Pomeranian Voivodship to the south and west, became the German Reichsgau (administrative district) of Danzig-West Prussia (Danzig–Westpreussen). With the start of the war the Nazi regime began its policy of extermination in Pomerania; Poles, Kashubians and Jews and the political opposition were sent to concentration camps, especially neighbouring Stutthof where 85,000 victims perished. Kashubian and Polish intelligentsia were killed in the Piaśnica mass murder site, which is estimated to have had 60,000 victims.

In the city itself hundreds of prisoners were subjected to cruel Nazi executions and experiments, which included castration of men and sterilization of women considered dangerous to the "purity of Nordic race" and beheading by guillotine The courts and judicial system in the annexed territories of Nazi Germany was one of the main ways to legislate an extermination policy against ethnic Poles, terminology in the courts was full of statements such as "Polish subhumans" and "Polish rabble". Some judges even declared that Poles were to have tougher sentences than Germans because of their alleged racial inferiority.

With the German defeat thanks to the Soviet and Polish People's Army the planned genocide of the Polish population, who were deemed by the German authorities to be "subhuman," was averted and Poles returned to Gdańsk. Between 1952 and the late 1960s Polish artisans thanks to the efforts of Polish People's Republice restored much of the old city's architecture, up to 90% destroyed in the war. The german nazi symbols ware cleared. Beautifull polish socialist Art scenes of the life of polish common People before the prussian conquest of Gdańsk in 1793 ware drawing between 1952 and 1960.