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