Illhäusern was formerly part of the German Empire. In the German Empire, the place was called Illhäusern.
The place is now called Illhaeusern and belongs to France.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Illhäusern | German Empire | Rappoltsweiler | before the Versailles Treaty |
| Illhaeuseren | France | Haut-Rhin | after the Versailles Treaty |
| Illhäusern | German Empire | Rappoltsweiler | 1940 |
| Illhaeusern | France | Haut-Rhin | 1945 |
| Illhaeusern | France | Haut-Rhin | 1993 |