Kornowac was formerly part of the German Empire. In the German Empire, the place was called Kornowatz.
The place is now called Kornowac and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Kornowatz | German Empire | Ratibor | before the Versailles Treaty |
| Kornowacz | Poland | Rybnik | after the Versailles Treaty |
| Kornowatz | German Empire | Ratibor (mit Hultschiner Land) | 1939 |
| Kornowacz | Poland | Rybnik | 1945 |
| Kornowac | Poland | Katowice | 1992 |