[citation needed] In the 14th century, papal verdicts ordered the restoration of the town and region to Poland, however, the Teutonic Knights did not comply and continued to occupy it.

[6] During the era of the Teutonic Knights, Graudenz had become a distinguished trade center in particular for textiles and agricultural products including grain.

[citation needed] Around 1454, Graudenz had already reached about the same level of economic development as other towns in the western part of the State of the Teutonic Order, such as Danzig (Gdańsk), Elbing (Elbląg), Thorn (Toruń), Marienburg (Malbork), Kulm (Chełmno), Konitz (Chojnice), Neumark (Nowe Miasto Lubawskie) and Preußisch Stargard (Starogard Gdański).

[citation needed] In 1440, the city co-founded the Prussian Confederation which opposed the Monastic State of the Teutonic Knights.

[citation needed] In 1522, Nicolaus Copernicus, who aside from his astronomical work was also an economist, presented his treatise Monetae cudendae ratio in Grudziądz.

[citation needed] In 1597 King Sigismund III Vasa gave order that the Protestants had to return all churches taken over by them in the past to the Catholics, including all accessories.

For a while, they used once more the vacant Holy Spoirit Church, until in 1624 this building together with the hospital had to be handed over to nuns of the Order of Saint Benedict for the purpose of founding an affiliated institution.

With the improvement of the railway network in Germany, Graudenz transiently lost its meaning as an important trading place for grain.

The Imperial German Navy named a light cruiser class and its lead ship, the SMS Graudenz, after the city.

[citation needed] Around the turn to the 20th century, Graudenz had become an important cultural centre in east Germany with numerous schools, municipal archives and a museum.

In 1832, also 249 Polish insurgents the November Uprising were imprisoned by the Prussians in the local fortress and subjected to forced labour, malnutrition, beatings and insults.

[15] Released prisoners who left Europe formed the Gromada Grudziądz in Portsmouth, England in 1835 as part of the Great Emigration movement.

[21] Laws were passed aimed at Germanisation of the Polish inhabited areas and 154,000 colonists were settled by the Prussian Settlement Commission before World War I.

It advocated the social and economic emancipation of rural society and opposed Germanization – publishing articles critical of Germany.

[39] The Polish authorities, supported by the public (e.g. the "explicitly anti-German" Związek Obrony Kresów Zachodnich), initiated a number of measures to further Polonization.

Fearful of a re-Germanization of the city, the Polish paper "Słowo Pomorskie" (23.19.1923) criticized the authorities of Grudziądz for tolerating the local German amateur theatre "Deutsche Bühne".

[41] Created before the war, its actors were mostly German officers stationed with the local garrison[42] The mayor responded by pointing out that the theatre was being monitored because of suspected "anti-state activities".

Grudziądz's economic potential was featured at the First Pomeranian Exhibition of Agriculture and Industry in 1925, officially opened by Stanisław Wojciechowski, President of the Second Polish Republic.

The Grudziądz Centre of Cavalry Training educated many notable army commanders, including future Polish resistance hero Witold Pilecki.

The discovery caused outrage and calls to dismiss Hilgendorf due to his irredentist beliefs[50] In November 1933 two German craftsmen were killed by a Polish mob during a local election campaign.

[51] They also carried out mass searches of Polish courthouses, organizations, police stations, etc., and seized large amounts of grain, textiles, coffee, equipment, and even homing pigeons.

[51] On 7 September, 25 Polish citizens were detained as hostages[52] – priests, teachers and other members that enjoyed the respect of local society.

They were threatened with execution if any harm came to the ethnic Germans from the city who were detained and held by the Polish authorities during the invasion of Poland.

Alongside the military and Einsatzgruppen administration, the first structures of Selbstschutz were established – a paramilitary formation of members of the German minority in the region.

[60][61] In October 1939, Selbstschutz created an internment camp for Poles seeking to restore Polish independence, whose commandant was a local German Kurt Gotze.

[61] Teachers, officials, social workers, doctors, merchants, members of patriotic organisations, lawyers, policemen, farmers and 150 Polish priests were held in this camp.

The "court" comprised: Kurt Gotze, Helmut Domke, Horst Kriedte, Hans Abromeit (owner of a drugstore), Paul Neuman (barber).

[62][64] Those sentenced to death were mostly executed through shooting by the Selbstschutz in Księże Góry near Grudziądz; in October and November 1939 several hundred people were murdered there and their bodies buried in five mass graves.

[65] On 29 October 1939 a unit of Selbstschutz mass-murdered ten Polish hostages as revenge for posters that had appeared in the city calling for resistance against Nazi occupation.

Soviet Major Lev Kopelev participated in those battles and covered the final surrender of the German garrison in his book "To Be Preserved Forever".