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