Zalesie (Bz. Posen) was formerly part of the German Empire. In the German Empire, the place was called Sahlau.
The place is now called Zalesie and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Zalesie (Bz. Posen) | German Empire | Gostyn | before the Versailles Treaty |
| Zalesie | Poland | Gostyń | after the Versailles Treaty |
| Zalesie | German Empire | Gostingen | 1939 |
| Sahlau | German Empire | Gostingen | 1939 |
| Zalesie | Poland | Gostyń | 1945 |
| Zalesie | Poland | Leszno | 1992 |