Łęg was formerly part of the German Empire. In the German Empire, the place was called Lengen.
The place is now called Łęg and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Leng | German Empire | Pleschen | before the Versailles Treaty |
| Łęg | Poland | Jarocin | after the Versailles Treaty |
| Lengen | German Empire | Jarotschin | 1939 |
| Łęg | Poland | Pleszew | 1945 |
| Łęg | Poland | Kalisz | 1992 |