Erbreichsplan

The Erbreichsplan (German for Plan for a Hereditary Empire) was a plan formed by the Emperor Henry VI to change the Holy Roman Empire from an elective to a hereditary monarchy. Such a move would have drastically changed the character of the Empire, but Henry was unable to garner sufficient support for the plan and it was ultimately forgotten.

Henry, who had been crowned Holy Roman Emperor in 1191, was known for being highly aggressive in guarding and expanding the rights of the imperial crown. In 1194 he also invaded the Kingdom of Sicily and conquered it from its king, William III. That same year his wife Constance gave birth to a son, Frederick II, who would, if all went well, inherit both the Imperial title and the Kingdom of Sicily. It was Henry's dream to have the Empire and Sicily permanently unified under the House of Hohenstaufen.

Unfortunately for Henry's plans, however, the Empire was an elective monarchy, meaning that the Hohenstaufens' hold on the imperial title depended on a favorable election by the princes after the death of every Emperor. The dynasty's hold on the empire could never be secure as long as the princes controlled the electoral process. Henry was aware of developments in other European countries such as France, where the principle of hereditary monarchy was firmly established and the strength of the crown was increasing. Henry ultimately decided on pursuing a way to change the imperial title into a hereditary one, and attempted to gain the support of the princes of the Empire.

The secular princes, for their part, feared Henry's extensive powers. Although hereditary succession for princes (Leihezwang) had become customary within the Empire, it was still not a formal right and on multiple occasions Henry refused to enfeoff the direct heir of a deceased prince with the latter's territory (the most notable example of this being Henry's seizure of the Margraviate of Meissen in 1195 as a vacant fief after the death of Albrecht the Proud, rather than enfeoffing Albrecht's brother Dietrich I with the margraviate). As a result, the princes were nervous about their rights of inheritance and were willing to grant certain concessions to the Emperor in exchange for the preservation of these rights.

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