After the joint German-Soviet invasion of Poland, which started World War II in September 1939, the town was occupied by Germany until 1945.

[5] The expellees were held for several days in a transit camp in the nearby village of Kowanówko, where they were robbed of money and valuables, and then they were deported in freight trains to Sokołów Podlaski in the General Government in the more-eastern part of German-occupied Poland.

[6] Some of the Poles expelled in 1940 from the nearby Chodzież and Szamotuły counties were enslaved as forced labour in the town's vicinity.

[8] In August 1944, the Germans carried out mass arrests of local members of the Home Army, the leading Polish underground resistance organization.

[9] Among the historic landmarks of Oborniki are:[3] Oborniki is one of the production sites of the Greater Poland liliput cheese (ser liliput wielkopolski), a traditional regional Polish cheese, protected as a traditional food by the Ministry of Agriculture and Rural Development of Poland.