The counts of Celje owned around 20 castles in Slovenia

The year 1456 changed the course of Slovenian history. In November of that year, the last count of Celje was assassinated in Belgrade. The counts of Celje had become one of the most powerful families in the region. The family owned around 20 castles in Slovenia alone, and were connected to royal families around Europe. In fact, they were a serious rival to the House of Habsburg. But that rivalry ended with the death of Ulrich II in Belgrade. There were no male heirs and the inheritance of the Counts of Celje passed to the House of Habsburg, which would then dominate Slovenian lands for centuries to come.