Troja was formerly part of the German Empire. In the German Empire, the place was called Troja (Praha-Troja).
The place is now called Troja (Praha-Troja) and belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Troja | Austro-Hungary | Karolinenthal | before the Treaty of Saint-Germain |
| Troja | Czechoslovakia | Praha, Hlavní město/Prag | after the Treaty of Saint-Germain |
| Troja (Prag-Troja) | German Empire | Prag, Hauptstadt | 1939 |
| Troja (Praha-Troja) | German Empire | Prag, Hauptstadt | 1939 |
| Troja | Czechoslovakia | Praha, Hlavní město | 1945 |
| Troja (Praha-Troja) | Czechoslovakia | Praha, Hlavní město | 1992 |
| Troja (Praha-Troja) | Czech Republic | Praha-město | 1993 |