Slawecin was formerly part of the German Empire. In the German Empire, the place was called Slawencin.
The place is now called Sławęcin and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Slawecin | Russian Empire | Vloclavek | 1914 |
| Sławęcin | Poland | Włocławek | 1921 |
| Slawencin | German Empire | Leslau | 1939 |
| Sławęcin | Poland | Włocławek | 1945 |
| Sławęcin | Poland | Włocławek | 1992 |