Rojau was formerly part of the German Empire. In the German Empire, the place was called Royau.
The place is now called Rájov and belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Rojau | Austro-Hungary | Marienbad | before the Treaty of Saint-Germain |
| Rájov | Austro-Hungary | Marienbad | before the Treaty of Saint-Germain |
| Rájov | Czechoslovakia | Mariánské Lázně | after the Treaty of Saint-Germain |
| Rojau | Czechoslovakia | Mariánské Lázně | after the Treaty of Saint-Germain |
| Rojau | German Empire | Marienbad | 1938 |
| Royau | German Empire | Marienbad | 1938 |
| Rájov | Czechoslovakia | Mariánské Lázně | 1945 |
| Rájov | Czechoslovakia | Cheb | 1992 |
| Rájov | Czech Republic | Cheb | 1993 |