Księży Lasek was formerly part of the German Empire. In the German Empire, the place was called Fürstenwalde.
The place is now called Księży Lasek and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Fürstenwalde | German Empire | Ortelsburg | 1939 |
| Księży Lasek | Under Polish administration | Szczytno | 1945 |
| Księży Lasek | Poland | Ostrołęka | 1992 |