NN was formerly part of the German Empire. In the German Empire, the place was called Sblong.
The place is now called NN and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| NN (Sblong) | Russian Empire | Vloclavek | 1914 |
| NN | Poland | Włocławek | 1921 |
| Sblong | German Empire | Leslau | 1939 |
| Zbląg | Poland | Radziejów | 1945 |
| NN | Poland | Włocławek | 1992 |