World War II thumb|Psychiatric hospital in the Kocborowo district During the joint German-Soviet invasion of Poland, which started World War II in September 1939, the city was invaded by Nazi Germany, and then the German Einsatzkommando 16 and SS Wachsturmbann "Eimann" entered the city to commit various crimes against Poles. Under German occupation, the city was annexed into the newly formed Regierungsbezirk Danzig in the new province of Reichsgau Danzig-West Prussia. The Polish population was subjected to mass arrests, imprisonment, tortures, massacres, expulsions, deportations to concentration camps and to forced labour.
World War II thumb|Psychiatric hospital in the Kocborowo district During the joint German-Soviet invasion of Poland, which started World War II in September 1939 the city was invaded by Nazi Germany, and then the German Einsatzkommando 16 and SS Wachsturmbann "Eimann" entered the city to commit various crimes against Poles. Under German occupation, the city was annexed into the newly formed Regierungsbezirk Danzig in the new province of Reichsgau Danzig-West Prussia. The Polish population was subjected to mass arrests, imprisonment, tortures, massacres, expulsions, deportations to concentration camps and to forced labour