House of Nassau-Weilburg

The House of Nassau-Weilburg, a branch of the House of Nassau, ruled a division of the County of Nassau, which was a state in what is now Germany, then part of the Holy Roman Empire, from 1344 to 1806.

House of Nassau-Weilburg
Parent house	House of Nassau[1][2]
Founded	1344 (1344)
Founder	John I of Nassau-Weilburg
Current head	Grand Duke Henri (Cognatic)
Titles	Grand Duke of Luxembourg Prince of Nassau-Weilburg Duke of Nassau Count of Nassau-Weilburg
Style(s)	His/Her Royal Highness
Estate(s)	of Nassau and Luxembourg

On July 17, 1806, on the dissolution of the Holy Roman Empire, the counties of Nassau-Usingen and Nassau-Weilburg both joined the Confederation of the Rhine. Under pressure from Napoleon, both counties merged to become the Duchy of Nassau on August 30, 1806, under the joint rule of Prince Frederick August of Nassau-Usingen and his younger cousin, Prince Frederick William of Nassau-Weilburg. As Frederick August had no heirs, he agreed that Frederick William should become the sole ruler after his death. However, Frederick William died from a fall on the stairs at Schloss Weilburg on January 9, 1816, and it was his son William who later became duke of a unified Nassau.

The sovereigns of this house afterwards governed the Duchy of Nassau until 1866. Since 1890, they have reigned the Grand Duchy of Luxembourg.