Tvrdín was formerly part of the German Empire. In the German Empire, the place was called Twrdina.
The place is now called Tvrdín and belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Twrdina | Austro-Hungary | Dux | before the Treaty of Saint-Germain |
| Tvrdín | Austro-Hungary | Dux | before the Treaty of Saint-Germain |
| Tvrdín | Czechoslovakia | Duchcov | after the Treaty of Saint-Germain |
| Twrdina | Czechoslovakia | Duchcov | after the Treaty of Saint-Germain |
| Twrdina | German Empire | Bilin | 1938 |
| Tvrdín | Czechoslovakia | Bílina | 1945 |
| Tvrdín | Czechoslovakia | Teplice | 1992 |
| Tvrdín | Czech Republic | Teplice | 1993 |