Osek was formerly part of the German Empire. In the German Empire, the place was called Osek.
The place is now called Osek and belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Wosek | Austro-Hungary | Rokycan | before the Treaty of Saint-Germain |
| Osek | Austro-Hungary | Rokycan | before the Treaty of Saint-Germain |
| Osek | Czechoslovakia | Rokycany | after the Treaty of Saint-Germain |
| Wosek | German Empire | Rokitzan | 1939 |
| Osek | German Empire | Rokitzan | 1939 |
| Osek | Czechoslovakia | Rokycany | 1945 |
| Osek | Czechoslovakia | Rokycany | 1992 |
| Osek | Czech Republic | Rokycany | 1993 |