Nassau-Dietz was raised to the status of a principality, becoming the Principality of Nassau-Dietz. From this point, the lord of the area became the 'Prince of Nassau-Dietz'. The counties of Nassau-Dietz and Spiegelberg along with the Frisian governorship were then successively taken over by his sons Heinrich Casimir I and Wilhelm Friedrich. When Prince William of Orange became King of England, Scotland, and Ireland (etc.) in February 1689, he declared Prince John William Friso as titular Prince of Orange. In 1702, Prince John William merged three of his titles into one: Prince of Orange, Prince of Nassau-Dietz, and Stadtholder of Friesland and Groningen into the Prince of Orange-Nassau. Lords The Counts, later Princes of Nassau-Dietz included: Footnotes References States and territories established in 1606 States and territories disestablished in the 1700s Lower Rhenish-Westphalian Circle History of Rhineland-Palatinate Principalities of the Holy Roman Empire 1606 establishments in Europe 1707 disestablishments in Europe Former monarchies of Europe