Duke Alexander of Württemberg (1804–1885) was the father of Prince Francis, Duke of Teck. In 1835, he married, morganatically, Claudine Rhédey von Kis-Rhéde (1812-1841), by whom he fathered three children: Claudine, Francis and Amalie. His wife was created Countess of Hohenstein in her own right and, following the rules of morganatic marriages, the children inherited their mother’s title as Count or Countess of Hohenstein from birth. They had no rights through their father to any royal status or inheritance. In 1841, his wife was killed, run over by horse, and this was such a devastating blow to Alexander that he became mentally unstable, a condition which lasted for the rest of his life. He died in 1885 at the age of 80.
Duke Alexander’s father was Duke Ludwig-Friedrich of Württemberg, brother of King Friedrich I of Württemberg and Empress Maria Feodorovna of Russia. Duke Alexander’s mother was Henrietta of Nassau-Weilburg, a great-granddaughter of King George II of Great Britain through his eldest daughter Anne, Princess Royal and Princess of Orange who married Willem IV, Prince of Orange-Nassau and the first hereditary Stadtholder of the United Provinces of the Netherlands.
Duke Ludwig-Friedrich was a general in the cavalry. He was briefly a high ranking commander in the Army of the Polish-Lithuanian Commonwealth. Duke Ludwig-Friedrich was also appointed the commander of the Grand Duchy of Lithuania’s army. He betrayed the Commonwealth by refusing to fight against Russian troops throughout the Polish–Russian War of 1792, while feinting illness. For his betrayal he was dismissed from his post, but never persecuted. His Polish wife, Maria Wirtemberska, divorced him shortly afterward after his treason became public knowledge.
On 28 January 1797 in Hermitage, near Bayreuth, Louis Frederick was married to Princess Henriette of Nassau-Weilburg (then of Nassau), daughter of Charles Christian, Duke of Nassau-Weilburg and Princess Carolina of Orange-Nassau. The couple had five children:
1. Duchess Maria Dorothea Luise Wilhelmine Karoline of Württemberg (1 November 1797 – 30 March 1855); granted the style Royal Highness on 26 December 1805; married in 1819 Archduke Joseph of Austira, Palatine of Hungary (9 March 1776 – 13 January 1847).
2. Duchess Amalie of Württemberg (28 June 1799 – 28 November 1848); granted the style Royal Highness on 26 December 1805; married in 1817 Joseph, Duke of Saxe-Altenburg (27 August 1789 – 25 November 1868).
3. Duchess Pauline of Württemberg (4 September 1800 – 10 March 1873); granted the style Royal Highness on 26 December 1805; married in 1820 her first cousin, Wilhelm I of Wurttemberg.
4. Duchess Elisabeth of Württemberg (27 February 1802 – 5 December 1864); granted the style Royal Highness on 26 December 1805; married in 1830 Prince Wilhelm, Grand-Ducal Prince and Margrave von Baden (8 April 1792 – 11 October 1859).
Duke Alexander of Württemberg (9 September 1804 – 4 July 1885); granted the style Royal Highness on 26 December 1805; married, morganitically, on 2 May 1835, Countess Claudine Rhédey von Kis-Rhéde, and had issue (21 September 1812 – 1 October 1841); founded the second branch of the House of Württemberg, known as the Dukes of Teck. The Dukes of Teck settled in the United Kingdom and with the change in titles in 1917, when king George V relinquished all German titles, the Teck family became the Cambridge family.
I mention the siblings of Duke Alexander of Württemberg to show case that the Cambridge family has distant cousins throughout German royal and noble houses. If you follow the family tree through Duke Alexander’s maternal grandmother, Princess Carolina of Orange-Nassau, you will find your way into various royal houses such as the Dutch royal house leading to Willem I The Silent, Prince of Orange, considered founder of the modern state of the Netherlands. Other ancestors of Duke Alexander was King George II of Great Britain (a German prince of the House of Hanover and Brunswick) and his wife Caroline of Brandenburg-Ansbach, who was the granddaughter of Albert II, Margrave of Brandenburg-Ansbach. If you follow the Brandenburg-Ansbach line you will eventually arrive at King Christian I of Denmark. Another prominent ancestor to the Earl of Athlone is King Friedrich I of Prussia.
Even though the Earl of Athlone’s mother, Princess Mary-Adelaide of Cambridge, was also ethnically German as a member of the House of Hanover, her son was very German through his father’s Württemberg heritage. This does raise the question about nationality verse ethnicity which are both human constructs. The Earl of Athlone was born and raised in the UK and culturally was every inch British despite the fact that his ancestors came from Germany.