Kwidzyn (Kfee-dzin [ˈkfʲid͡zɨn]; German: Marienwerder; Latin: Quedin; Old Prussian: Kwēdina) is a town in northern Poland on the Liwa River.

St. Dorothea of Montau lived in Marienwerder from 1391 until her death in 1394; future pilgrims visiting her shrine would contribute to the flourishing economy.

[5] Upon the request of the organization in 1454 Polish King Casimir IV Jagiellon incorporated the region and town to the Kingdom of Poland,[6] and the Thirteen Years' War broke out.

[9] In 1618 the ducal rights were inherited by the Brandenburg branch of the House of Hohenzollern, remaining under Polish suzerainty.

In 1657 the Brandenburg dukes severed ties with the Polish crown and in 1701 elevated their realm to the sovereign Kingdom of Prussia.

In 1772, the Marienwerder district was integrated into the newly established Prussian Province of West Prussia, which consisted mostly of territories annexed in the First Partition of Poland.

This population was composed mostly of Lutheran inhabitants, many of whom were engaged in trades connected with the manufacturing of sugar, vinegar and brewing as well as dairy farming, fruit growing and the industrial construction of machines.

[15] On May 16, 1920, the largest Polish plebiscite demonstration in Powiśle took place in the town, and Poles had to organize defenses against attacks by German militias.

[16] According to Polish sources there was German electoral fraud[17] resulted in 7,811 votes given to remain in East Prussia, and therefore Germany, and only 362 for Poland.

[19] The Germans, especially the Hitler Youth, repeatedly harassed and attacked Polish students and devastated the school.

[21] The German police surrounded the Polish school and arrested its principal Władysław Gębik, 13 teachers, other staff and 162 students, who were imprisoned in Tapiau (today Gvardeysk),[22] and then deported elsewhere.

[22] Nazi Germany co-formed the Einsatzgruppe V in the town, which then entered several Polish cities, including Grudziądz, Ciechanów, Łomża and Siedlce, to commit various atrocities against Poles during the German invasion of Poland, which started World War II.

[27] After World War II, the town became again part of Poland under the terms of the Potsdam Agreement, although with a Soviet-installed communist regime, which stayed in power until the 1980s.

Other sights include the Appellate Court for Kwidzyn County, the town hall, the Holy Trinity church, the Saint Padre Pio chapel, various government buildings and old townhouses.