Rensko was formerly part of the German Empire. In the German Empire, the place was called Renzing.
The place is now called Reńsko and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Rensko | German Empire | Schmiegel | before the Versailles Treaty |
| Reńsko | Poland | Kościan | after the Versailles Treaty |
| Renzing | German Empire | Kosten (Wartheland) | 1939 |
| Reńsko | Poland | Kościan | 1945 |
| Reńsko | Poland | Poznań | 1992 |