Arnau was formerly part of the German Empire. In the German Empire, the place was called Arnau.
The place is now called Hostinné and belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Arnau | Austro-Hungary | Hohenelbe | before the Treaty of Saint-Germain |
| Hostinné | Austro-Hungary | Hohenelbe | before the Treaty of Saint-Germain |
| Hostinné | Czechoslovakia | Vrchlabí | after the Treaty of Saint-Germain |
| Arnau | Czechoslovakia | Vrchlabí | after the Treaty of Saint-Germain |
| Arnau | German Empire | Hohenelbe | 1938 |
| Hostinné | Czechoslovakia | Vrchlabí | 1945 |
| Hostinné | Czechoslovakia | Trutnov | 1992 |
| Hostinné | Czech Republic | Trutnov | 1993 |