Blaukrug was formerly part of the German Empire. In the German Empire, the place was called Blaukrug.
The place is now called Over Blåkrog and belongs to Denmark.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Blaukrug | German Empire | Apenrade | before the Versailles Treaty |
| Blaakrog | Denmark | Aabenraa | after the Versailles Treaty |
| Over Blåkrog | Denmark | Sønderjylland | 1993 |