Wasserau was formerly part of the German Empire. In the German Empire, the place was called Wasserau.
The place is now called Ostrov and belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Wasserau | Austro-Hungary | Bischofteinitz | before the Treaty of Saint-Germain |
| Bezvěrov | Austro-Hungary | Bischofteinitz | before the Treaty of Saint-Germain |
| Bezvěrov | Czechoslovakia | Horšovský Týn | after the Treaty of Saint-Germain |
| Wasserau | Czechoslovakia | Horšovský Týn | after the Treaty of Saint-Germain |
| Wasserau | German Empire | Bischofteinitz | 1938 |
| Bezvěrov | Czechoslovakia | Horšovský Týn | 1945 |
| Ostrov | Czechoslovakia | Domažlice | 1992 |
| Ostrov | Czech Republic | Domažlice | 1993 |