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