Friedrich August I, Duke of Nassau

Friedrich August, Duke of Nassau, Prince of Nassau-Usingen (23 April 1738 in Usingen – 24 March 1816 in Wiesbaden) was the last Prince of Nassau-Usingen and, jointly with his cousin, Friedrich Wilhelm of Nassau-Weilburg, first Duke of Nassau. He died without surviving male issue and was succeeded by his cousin's son, Wilhelm.

Biography Early life Friedrich August, born in Usingen, was a younger son of Prince Charles of Nassau-Usingen and Princess Christine Wilhelmine of Saxe-Eisenach (daughter of John William III, Duke of Saxe-Eisenach). From 1744, he lived with his parents in Schloss Biebrich in Wiesbaden. He followed a military career in the army of the Holy Roman Empire and served in the Seven Years' War. In 1790, he became a Field Marshal.

Ruler of Nassau On 17 May 1803, he succeeded as the Prince of Nassau-Usingen when his elder brother, Charles William, died without male heirs. On 6 July 1806, he joined the Confederation of the Rhine in order to prevent Napoleon from annexing the principality. Shortly thereafter, on 30 August 1806, he agreed with his cousin Friedrich Wilhelm of Nassau-Weilburg that their territories should be united into a single Duchy of Nassau with Frederick Augustus as the first duke and Frederick William as co-ruler. Since Friedrich August's sons had died young, it was also agreed that the combined duchy and sole rulership would pass to the heir of the Nassau-Weilburg line.

After Napoleon's defeat at the Battle of Leipzig, Friedrich August joined in the allies fighting against the French emperor. Nassau's troops fought under the command of Arthur Wellesley, 1st Duke of Wellington at the Battle of Waterloo. At the Congress of Vienna, the unification of the Duchy of Nassau was approved and the duchy joined the German Confederation. Friedrich Wilhelm (Biebrich, 30 July 1780 - Biebrich, 18 August 1780). Luise Maria (Usingen, 18 July 1782 - Biebrich, 27 June 1812). Friederike Victoria (Usingen 21 February 1784 - Hannover, 18 July 1822), married to Count Ludwig Heinrich Klaus von Burgund. Friedrich Karl (Usingen, 17 June 1787 - Frankfurt am Main, 29 September 1787)

Ancestry