When German territory was given to Poland at the end of WWII, many names changed.
http://polandpoland.com/names_german_polish.html
I had a German colleague whose grandma was born in these lands (Silesia), and she was expelled to Germany after the war. After the iron curtain fell, she went back there to visit her old farm... Buildings, roads, and all names were gone - small rivers, cities, no place mark or road sign had any sense to her. The only things she could recognize were some landscapes and trees - she even found a tree nearby where her brother had a tire swing as a child.
The Polish people were cooperative and she could tour her old farm, even if no building from her time is left standing.
Similar issues in the Russian Kaliningrad Oblast, wiki lists german, russian and polish names:
https://en.wikipedia.org/wiki/List_of_inhabited_localities_in_Kaliningrad_Oblast