… our roots …
early 13th century a settlement was mentioned with this name at a lake there, named the CulmSEE ( = CulmLAKE) … and it was told that a wanderer who came from that settlement’s lake named himself Culmsee because those days family names where not common … and that’s why – very shortened – why “we” are named Culmsee or Kulmsee or in a variation Kolmsee / Colmsee, too, reasoned by the fact that C… / K… often were used synonymous (Latin) …
location of Culmsee in 1251 got city rights
since 20th century, finally after WWII, C/K got back its name Chełmża located at the lake named Jezioro Chełmżyńskie
As a fun and somewhat strange fact, the map I use as a background calls the lake “Culmseer See”, which is somewhat a Pleonasm (a duplication)