Kostbar was formerly part of the German Empire. In the German Empire, the place was called Kostbar.
The place is now called Kozibór and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Kostbar | German Empire | Thorn | before the Versailles Treaty |
| Kozibór | Poland | Toruń | after the Versailles Treaty |
| Kostbar | German Empire | Thorn | 1939 |
| Kozi Bór | Poland | Toruń | 1945 |
| Kozibór | Poland | Toruń | 1992 |