The city was officially annexed by Nazi Germany and incorporated into the Reichsgau Danzig-West Prussia . About 50 percent of members of the Jewish Community of Danzig had left the city within a year after a Pogrom in October 1937 , after the Kristallnacht riots in November 1938 the community decided to organize its emigration and in March 1939 a first transport to Palestine started . By September 1939 barely 1,700 mostly elderly Jews remained . In early 1941 , just 600 Jews were still living in Danzig , most of whom were later murdered in the Holocaust . Out of the 2,938 Jewish community in the city 1,227 were able to escape from the Nazis before the outbreak of war . Nazi secret police had been observing Polish minority communities in the city since 1936 , compiling information , which in 1939 served to prepare lists of Poles to be captured in Operation Tannenberg . On the first day of the war , approximately 1,500 ethnic Poles were arrested , some because of their participation in social and economic life , others because they were activists and members of various Polish organisations . On 2 September 1939 , 150 of them were deported to the Sicherheitsdienst camp Stutthof some from Danzig , and murdered . Many Poles living in Danzig were deported to Stutthof or executed in the Piaśnica forest
Operation Tannenberg
Operation Tannenberg
Gdańsk