NN was formerly part of the German Empire. In the German Empire, the place was called Janischau.
The place is now called NN and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| NN (Janischau) | German Empire | Marienwerder | before the Versailles Treaty |
| NN | Poland | Gniew | after the Versailles Treaty |
| Janischau | German Empire | Dirschau | 1939 |
| NN | Poland | Tczew | 1945 |
| NN | Poland | Gdańsk | 1992 |