During World War II, within today's town limits, the Germans established and operated a forced labour subcamp of the German military prison in Grudziądz in German-occupied Poland. In the final stages of the war the town's populace was evacuated by the Germans on January 21-22, and on January 24, 1945 the German administration left the town, which then fell to the Soviets. The first local Polish official was appointed in April 1945. Several months later the town was handed over to Poland, and the name "Dzierzgoń", based on an Old Prussian Zirgūni name, was restored. At the turn of 1945 and 1946, the Polish resistance movement carried out successful attacks against communists and Soviets, acquiring weapons, uniforms and money. The town was resettled by Poles from Polish areas annexed by the Soviet Union and Ukrainians expelled from southeast Poland in 1947. The former Roman Catholic Cloister is now a Ukrainian Eastern Rite Catholic Church.