The House of Nassau
1544: "Orange-Nassau" symbolized by adding the "Châlon-Orange" arms in an escutcheon
to the "Nassau" arms.
Nassau Castle was founded around 1100 by Count Dudo of Laurenburg (German: Dudo von Laurenburg), the founder of the House of Nassau. In 1120, Dudo's sons and successors, Counts Rupert I (German: Ruprecht; also translated as Rupert) and Arnold I, established themselves at Nassau Castle with its tower. They renovated and extended the castle complex in 1124.The Nassau family married into the family of the neighboring Counts of Arnstein (now Kloster Arnstein). His sons, Walram and Otto, split the Nassau possessions. The descendants of Walram were known as the Walram Line, and they became Dukes of Nassau and, in 1890, Grand Dukes of Luxembourg. This line also included Adolph of Nassau, who was elected King of the Romans in 1292. The descendants of Otto became known as the Ottonian Line, and they inherited parts of the County of Nassau, as well as properties in France and the Netherlands.
William the Silent
, Prince of Orange, leader of the Dutch War for Independence, and stadholder of Holland, Zeeland, and Utrecht.
The House of Orange-Nassau stems from the younger Ottonian Line. The first of this line to establish himself in the Netherlands was John I, Count of Nassau-Dillenburg, who married Margareta of the Marck. The real founder of the Nassau fortunes in the Netherlands was John's son, Engelbert I. He became counsellor to the Burgundian Dukes of Brabant, first to Anton of Burgundy, and later to his son Jan IV of Brabant. He also would later serve Philip the Good. In 1403, he married the Dutch noblewoman Johanna van Polanen and so inherited lands in the Netherlands, with the Barony of Breda as the core of the Dutch possessions and the family fortune.:35
A nobleman's power was often based on his ownership of vast tracts of land and lucrative offices. It also helped that much of the lands that the House of Orange-Nassau controlled sat under one of the commercial and mercantile centers of the world (see below under Lands and Titles. The importance of the family grew throughout the 15th and 16th centuries as they became councilors, generals and stadholders of the Habsburgs (see armorial of the great nobles of the Burgundian Netherlands and List of Knights of the Golden Fleece). Engelbert II of Nassau served Charles the Bold and Maximilian I, Holy Roman Emperor, who had married Charles's daughter Mary of Burgundy. In 1496, he was appointed stadtholder of Flanders and by 1498 he had been named President of the Grand Conseil. In 1501, Maximilian named him Lieutenant-General of the Seventeen Provinces of the Netherlands. From that point forward (until his death in 1504), Engelbert was the principal representative of the Habsburg Empire to the region. Hendrik III of Nassau-Breda was appointed stadtholder of Holland and Zeeland by Charles of Ghent in the beginning of the 16th century. Hendrik was succeeded by his son René of Châlon-Orange in 1538, who had inherited the principality of Orange and the title Prince of Orange from his maternal uncle Philibert of Chalon. René died prematurely on the battlefield in 1544. His possessions, including the principality of Orange and the title Prince of Orange, passed by his will as sovereign prince to his paternal cousin, William I of Orange. From then on, the family members called themselves "Orange-Nassau.":8:37:vol3,pp3-4:37,107,139