Bagna was formerly part of the German Empire. In the German Empire, the place was called Josefsberg.
The place is now called Bagna and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Josephsberg | German Empire | Konitz | before the Versailles Treaty |
| Bagna | Poland | Chojnice | after the Versailles Treaty |
| Josefsberg | German Empire | Konitz | 1939 |
| Bagna | Poland | Chojnice | 1945 |
| Bagna | Poland | Bydgoszcz | 1992 |