Kętrzyn was formerly part of the German Empire. In the German Empire, the place was called Rastenburg.
The place is now called Kętrzyn and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Rastenburg | German Empire | Rastenburg | 1939 |
| Kętrzyn | Under Polish administration | Kętrzyn | 1945 |
| Kętrzyn | Poland | Olsztyn | 1992 |