After World War I and the re-establishment of independent Poland, during the ongoing Polish-Soviet War, a plebiscite was held in parts of East Prussia and West Prussia on July 11, 1920 to determine whether the region was to remain in Germany or join the Second Polish Republic. In the Rosenberg district, 33,498 (96.9%) voted to remain in Germany and 1,073 (3.1%) voted for Poland. In the town itself, 2,430 votes were cast in favour of Germany and only 8 votes were cast in favour of Poland. Based on that result, the district, along with the town, was included in the Regierungsbezirk West Prussia within the Prussian Province of East Prussia in Germany.