Opoczki was formerly part of the German Empire. In the German Empire, the place was called Klein Ottingen.
The place is now called Opoczki and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Klein-Opok | German Empire | Inowrazlaw | before the Versailles Treaty |
| Opoczki | Poland | Inowrocław | after the Versailles Treaty |
| Klein Ottingen | German Empire | Hohensalza | 1939 |
| Opoczki | Poland | Aleksandrów Kujawski | 1945 |
| Opoczki | Poland | Włocławek | 1992 |