Chełmno is a town in northern Poland near the Vistula river with 18,915 inhabitants as of December 2021. It is the seat of the Chełmno Count…Chełmno is a town in northern Poland near the Vistula river with 18,915 inhabitants as of December 2021. It is the seat of the Chełmno County in the Kuyavian-Pomeranian Voivodeship. Due to its regional importance in the Middle Ages, the town gave its name to the entire area, Chełmno Land, the local Catholic diocese and Kulm law, a municipal form of government for cities and towns around Poland, including the current capital city of Warsaw.