Thommen was formerly part of the German Empire. In the German Empire, the place was called Thommen.
The place is now called Thommen and belongs to Belgium.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Thommen | German Empire | Malmedy | before the Versailles Treaty |
| Thommen | Belgium | Liège | after the Versailles Treaty |
| Thommen | German Empire | Malmedy | 1940 |
| Thommen | Belgium | Liège | 1945 |
| Thommen | Belgium | Lüttich/Liège | 1993 |