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