Piotrkowo was formerly part of the German Empire. In the German Empire, the place was called Piotrkowo.
The place is now called Piotrkowo and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Piotrkowo | Russian Empire | Mlava | 1914 |
| Piotrkowo | Poland | Mława | 1919 |
| Piotrkowo | German Empire | Mielau | 1939 |
| Piotrkowo | Poland | Nidzica | 1945 |
| Piotrkowo | Poland | Olsztyn | 1992 |