Chełmno land (Polish: ziemia chełmińska, German: Culmer Landⓘ or Kulmerland, reconstructed Old Prussian: Kulma) is a part of the historical region of Pomerelia, located in central-northern Poland.

It is located on the right bank of the Vistula river, from the mouth of the Drwęca (southern boundary) to the Osa (northern).

The Masovians were led by Masos, who left the Polish duke Boleslaw I and sought refuge with the Prussians.

By the 13th century the territory was subject to raids by pagan Old Prussians, who sacked Chełmno, the province's main town, in 1216.

[4] The Teutonic Order obtained an Imperial bull from Emperor Frederick II before entering Prussia.

[8] In 1454 the confederation started an uprising against the Teutonic Order and turned to Polish King Casimir IV Jagiellon with a request to reunite the region with Poland.

[11][12] In 1772 as a result of the First Partition of Poland, Chełmno Land (with the exception of Toruń, annexed in 1793) was seized by the Kingdom of Prussia.

[14] Following the Treaty of Versailles, Chełmno Land was returned to Poland in January 1920, after the Poles regained independence in 1918.

Following the invasion of Poland, which started World War II in September 1939, it was occupied by Nazi Germany and unilaterally annexed in October, however, lacking any international recognition.

mass arrests, imprisonment, slave labor, kidnapping of children, deportations to Nazi concentration camps and extermination.

Major sites of massacres of Poles in the region included Klamry, Łopatki, Barbarka, Brzezinki, Małe Czyste, Płutowo and Nawra.

[16] Nevertheless, the Polish resistance movement was still organized in the region, with Toruń being the seat of one of the six main commands of the Union of Armed Struggle in all of occupied Poland.