Wersk was formerly part of the German Empire. In the German Empire, the place was called Seedorf (Grenzmark).
The place is now called Wersk and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Wersk | German Empire | Flatow | before the Versailles Treaty |
| Seedorf (Kr. Flatow) | German Empire | Flatow | after the Versailles Treaty |
| Seedorf (Grenzmark) | German Empire | Flatow | 1939 |
| Wersk | Under Polish administration | Złotów | 1945 |
| Wersk | Poland | Piła | 1992 |