Aarø was formerly part of the German Empire. In the German Empire, the place was called Aarö.
The place is now called Årø (Haderslev-Årø) and belongs to Denmark.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Aarö | German Empire | Hadersleben | before the Versailles Treaty |
| Aarø | Denmark | Haderslev | after the Versailles Treaty |
| Årø (Haderslev-Årø) | Denmark | Sønderjylland | 1993 |