Nassau Family Pact

The Nassau Family Pact was a mutual pact of inheritance and succession made in 1783 by princes of the old European noble and sovereign family of Nassau. It confirmed that Salic Law was to operate in favor of all the agnatic lines of the family, specifically the two senior surviving lines which had originated in the Middle Ages, the Walramian and the Ottonian. The pact chiefly provided that in case of one of these lines becoming extinct, the other would succeed in its hereditary Nassau lands ("the main concept of the pact was that if either the Ottonian or Walramian male line would become extinct the other line would succeed").

There was a clause to provide for a so-called Semi-Salic continuation to the dynasty in an undefined way if both the lines were to die out in the male line ("also arranged for that in the absence of all male successors, females could succeed"). In case of the extinction of all male lines, the closest heir to the last male will succeed and in turn will be succeeded by the heirs of that closest one. If the closest heir happens to be a woman, the pact was silent about whether her husband receives rights or not. There was no precise stipulation as to what precisely was to happen after that closest heir: would the succession evolve to heirs general, or only to heirs male, and what would happen if that line also died out.

The pact was agreed to be applied to "Imperial fiefs" which meant those territories owned or acquired in the then Holy Roman Empire. The pact thus in 1890 determined the succession of the Grand Duchy of Luxembourg, a territory acquired into the dynasty only after the pact was sealed but which at the time had been a member of the German Confederation, a body that was regarded as the successor to the Holy Roman Empire. The pact did not apply to the succession in the Kingdom of the Netherlands, a state not regarded as formerly imperial. Luxembourg was thus inherited by the Weilburg branch, the only extant branch from that date onward.

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