Pieńki was formerly part of the German Empire. In the German Empire, the place was called Birkenhain.
The place is now called Pieńki and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Birkenhain | German Empire | Briesen | before the Versailles Treaty |
| Pieńki | Poland | Wąbrzeźno | after the Versailles Treaty |
| Birkenhain | German Empire | Briesen (Westpr.) | 1939 |
| Pieńki | Poland | Wąbrzeźno | 1945 |
| Pieńki | Poland | Toruń | 1992 |