Kammala jumla mai zuwa: Bayan mamayewar Jamus a 1939, an haɗa Poland Babba cikin Nazi Jamus, ta zama lardin da ake kira Reichsgau Posen, daga baya Reichsgau Wartheland ("Warthe" shine sunan Jamusanci na kogin Warta). An zalunci mutanen Poland, tare da tsoffin jami'ai da yawa da wasu waɗanda Nazi ke ganin abokan gaba ne aka ɗaure su ko kashe su, gami da sanannen sansanin taro na Fort VII a Poznań. An ayyana Poznań a matsayin birni mai ƙarfi "Festung" a ƙarshen yakin, wanda Red Army ya ɗauka a cikin
Yaƙin Poznań, wanda ya ƙare a ranar 22 ga Fabrairu, 1945.