Plęsy was formerly part of the German Empire. In the German Empire, the place was called Plensen.
The place is now called Plęsy and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Plensen | German Empire | Bartenstein (Ostpr.) | 1939 |
| Plęsy | Under Polish administration | Bartoszyce | 1945 |
| Plęsy | Poland | Olsztyn | 1992 |