Reichsdeputationshauptschluss
The "Almanach de Gotha" (followed by subsequent series) differentiates between three sections of "Hochadel": The first section listed Europe's sovereign houses, whether they reign(ed) as emperor, king, grand duke, duke or prince. The second section contain the Mediatized Houses of Germany which lost their semi-sovereignty within the Holy Roman Empire during the period of German mediatization between 1803 and 1815. The third section includes the titular princely and ducal houses of Europe that never ruled as sovereigns.