Wilhelm (Given names: Georg Wilhelm August Heinrich Belgicus; 14 June 1792, Kirchheimbolanden – 20/30 August 1839, Bad Kissingen) was joint sovereign Duke of Nassau, along with his father's cousin Frederick Augustus, reigning from 1816 until 1839. He was also sovereign Prince of Nassau-Weilburg from 1816 until its incorporation into the duchy of Nassau. Frederick Augustus died on 24 March 1816 and Wilhelm inherited the Usingen territories and became sole sovereign of the Duchy of Nassau. He is the father of Adolphe, Grand Duke of Luxembourg, and Queen Sophia of Sweden and Norway, consort of King Oscar II and a 3rd cousin of William III of the Netherlands, who left a surviving daughter to rule his main realm, but the crown of Luxembourg went through the male line, looking to 17 generations back, to pass to the Duke of Nassau and then his descendants. Biography Wilhelm was the eldest son of Frederick William, Duke of Nassau, and his wife, Burgravine Louise Isabelle of Kirchberg. With the Nassau troops, he was involved on the Seventh Coalition's side in the Battle of Waterloo against Napoleon. Duke of Nassau On 9 January 1816, he succeeded his father, Duke Frederick William, as the Prince of Nassau-Weilburg and joint Duke of Nassau with his cousin, Frederick Augustus, of the Nassau-Usingen branch of his family. When his cousin and co-Duke died on 24 March 1816, Wilhelm inherited the Usingen territories and became sole ruler of the Duchy of Nassau. He kept the title of Duke of Nassau for the rest of his reign. Marriages and children On 24 June 1813 in Weilburg, Wilhelm married his first wife, Princess Louise of Saxe-Altenburg (28 January 1794 Hildburghausen, Thüringen – 6 April 1825, Biebrich or Weilburg). She was a daughter of Frederick, Duke of Saxe-Altenburg (who, until 1826, had been the last Duke of Saxe-Hildburghausen) and his wife, Duchess Charlotte Georgine of Mecklenburg-Strelitz. They had eight children: Princess Auguste Luise Friederike Maximiliane Wilhelmine of Nassau-Weilburg (Weilburg, 12 April 1814 – Weilburg, 3 October 1814). Princess Therese Wilhelmine Friederike Isabelle Charlotte of Nassau-Weilburg (Weilburg, 17 April 1815 – Prague, 8 December 1871); married in Biebrich on 23 April 1837 Duke Peter of Oldenburg. Their grandson was the Imperial Russian General Grand Duke Nicholas Nikolaevich of Russia the Younger. Adolphe, Grand Duke of Luxembourg (24 July 1817 – 17 November 1905); the present Grand Ducal Family of Luxembourg, which became extinct in