The House of Orange-Nassau (in Dutch: Huis van Oranje-Nassau), a branch of the European House of Nassau, has played a central role in the political life of the Netherlands — and at times in Europe — since William I of Orange (also known as "William the Silent" and "Father of the Fatherland") organized the Dutch revolt against Spanish rule, which after the Eighty Years' War led to an independent Dutch state.
Several members of the house served during this war and after as governor or stadtholder (Dutch stadhouder) during the Dutch Republic. However, in 1815, after a long period as a republic, the Netherlands became a monarchy under the House of Orange-Nassau.
The dynasty was established as a result of the marriage of Hendrik III of Nassau-Breda from Germany and Claudia of Châlon-Orange from French Burgundy in 1515. Their son René inherited in 1530 the Principality of Orange from his mother's brother, Philibert of Châlon. As the first Nassau to be the Prince of Orange, René could have used "Orange-Nassau" as his new family name. However, his uncle, in his will, had stipulated that René should continue the use of the name Châlon-Orange. History knows him therefore as René of Châlon. After the death of René in 1544 his cousin William of Nassau-Dillenburg inherited all his lands. This "William I of Orange" - in English better known as William the Silent - became the founder of the House of Orange-Nassau.