Forst was formerly part of the German Empire. In the German Empire, the place was called Forst.
The place is now called NN and belongs to Slovenia.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Forst | Austro-Hungary | Gurkfeld/Krško | before the Treaty of Saint-Germain |
| Boršt | Austro-Hungary | Gurkfeld/Krško | before the Treaty of Saint-Germain |
| Boršt | Yugoslavia | Krško | after the Treaty of Saint-Germain |
| Forst | German Empire | Rann | 1941 |
| Boršt | Yugoslavia | Trbovlje | 1945 |
| Boršt | Yugoslavia | Socialistična rep. Slovenija | 1992 |
| NN | Slovenia | Slowenien | 1991 |