Kaplja was formerly part of the German Empire. In the German Empire, the place was called Kappel.
The place is now called Kapla and belongs to Slovenia.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Kappel | Austro-Hungary | Cilli/Celje | before the Treaty of Saint-Germain |
| Kaplja | Austro-Hungary | Cilli/Celje | before the Treaty of Saint-Germain |
| Kaplja | Yugoslavia | Celje | after the Treaty of Saint-Germain |
| Kappel | German Empire | Cilli | 1941 |
| Kapla | Yugoslavia | Celje | 1945 |
| Kapla | Yugoslavia | Socialistična rep. Slovenija | 1992 |
| Kapla | Slovenia | Slowenien | 1991 |