Øster-Gasse was formerly part of the German Empire. In the German Empire, the place was called Oster-Gasse.
The place is now called Øster Gasse and belongs to Denmark.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Oster-Gasse | German Empire | Hadersleben | before the Versailles Treaty |
| Øster-Gasse | Denmark | Tønder | after the Versailles Treaty |
| Øster Gasse | Denmark | Sønderjylland | 1993 |