Sieroczyn was formerly part of the German Empire. In the German Empire, the place was called Buschwinkel.
The place is now called Sieroczyn and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Buschwinkel | German Empire | Schlochau | before the Versailles Treaty |
| Buschwinkel | German Empire | Schlochau | after the Versailles Treaty |
| Buschwinkel | German Empire | Schlochau | 1939 |
| Sieroczyn | Under Polish administration | Człuchów | 1945 |
| Sieroczyn | Poland | Słupsk | 1992 |