First Cousins: King George III of the United Kingdom

by Susan Flantzer
© Unofficial Royalty 2019

King George III of the United Kingdom (1738 – 1820)

(All photos credits – Wikipedia unless otherwise noted)

King George III, the eldest son and the second child of Frederick, Prince of Wales and Princess Augusta of Saxe-Gotha-Altenburg, was born June 4, 1738, at Norfolk House in St. James’s Square in London, England. His paternal grandparents were King George II of Great Britain and Princess Caroline of Brandenburg-Ansbach, generally known as Caroline of Ansbach. His maternal grandparents were Friedrich II, Duke of Saxe-Gotha-Altenburg and Princess Magdalena Augusta of Anhalt-Zerbst.

When George III was thirteen-years-old, his father died at the age of 44. George became heir to the throne and was created Prince of Wales and Earl of Chester. Nine years later, King George II died and his grandson succeeded him as King George III.  George III married Charlotte of Mecklenburg-Strelitz.  Their marriage was a very happy one and George remained faithful to Charlotte. Between 1762 – 1783, Charlotte gave birth to fifteen children, all of whom survived childbirth. Only two of the children did not survive childhood. The only disruption in the family’s domestic lives were George’s attacks of illness. There has been speculation that King George suffered from porphyria.

King George III is the longest-reigning British king, having reigned for 59 years, 96 days. His length of reign is surpassed only by two queens, his granddaughter Queen Victoria and his great-great-great-great-granddaughter Queen Elizabeth II, the longest-reigning British monarch.

King George III shared his 29 first cousins with his eight siblings: Princess Augusta, Duchess of Brunswick; Prince Edward, Duke of York; Princess Elizabeth; Prince William Henry, Duke of Gloucester; Prince Henry, Duke of Cumberland; Princess Louisa; Prince Frederick; and Princess Caroline Matilda, Queen of Denmark and Norway.

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Paternal Aunts and Uncles Of King George III: Children of King George II of Great Britain and Princess Caroline of Brandenburg-Ansbach

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Maternal Aunts and Uncles of King George III: Children of Friedrich II, Duke of Saxe-Gotha-Altenburg and Princess Magdalena Augusta of Anhalt-Zerbst

  • Sophie of Saxe-Gotha-Altenburg (1697 – 1703), died in childhood of smallpox
  • Friedrich III, Duke of Saxe-Gotha-Altenburg (1699 – 1772), married Luise Dorothea of Saxe-Meiningen, had four sons and two daughters
  • Wilhelm of Saxe-Gotha-Altenburg (1701 – 1771), married Anna of Holstein-Gottorp, no children
  • Karl Friedrich of Saxe-Gotha-Altenburg (1702 – 1703), died in infancy of smallpox
  • Johann August of Saxe-Gotha-Altenburg (1704 – 1767), married Louise Reuss of Schleiz, the widow of his brother Christian Wilhelm, had two daughters
  • Christian of Saxe-Gotha-Altenburg (born and died 1705), died in early infancy of smallpox
  • Christian Wilhelm of Saxe-Gotha-Altenburg (1706 – 1748), married Luise Reuss of Schleiz, no children
  • Ludwig Ernst of Saxe-Gotha-Altenburg (1707 – 1763), unmarried, military career
  • Emanuel of Saxe-Gotha-Altenburg (1709 – 1710), died in infancy
  • Moritz of Saxe-Gotha-Altenburg (1711 – 1777), unmarried, military career
  • Sophie of Saxe-Gotha-Altenburg (born and died 1712), died in infancy
  • Karl of Saxe-Gotha-Altenburg (1714 – 1715), died in infancy
  • Friederike of Saxe-Gotha-Altenburg, Duchess of Saxe-Weissenfels  (1715 – 1775), married Johann Adolf II, Duke of Saxe-Weissenfels, had four sons and one daughter
  • Magdalena Sibylle of Saxe-Gotha-Altenburg (born and died 1718), died in infancy
  • Johann Adolf of Saxe-Gotha-Altenburg (1721 – 1799), married morganatically Marie Maximiliane Elisabeth Schauer, had two sons and one daughter

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PATERNAL FIRST COUSINS

Paternal First Cousins: Children of Anne, Princess Royal and Willem IV, Prince of Orange

Carolina of Orange-Nassau, Princess of Nassau-Weilburg (1743 – 1787)

Carolina married Karl Christian, Prince of Nassau-Weilburg and had six sons and five daughters. Her father had died when she was eight-years-old and her three-year-old brother succeeded as Willem V, Prince of Orange. Willem would not reach his majority for fifteen years and until then he had a series of four regents. Carolina served as the last regent.

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Anna of Orange-Nassau (born and died 1746)

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Willem V, Prince of Orange (1748 – 1806)

Willem was the only son of Anne, Princess Royal and Willem IV, Prince of Orange. His father died when he was three-years-old Willem IV. Willem would not reach his majority for fifteen years and until then he had a series of four regents. Willem married Princess Wilhelmina of Prussia, daughter of Prince Augustus William of Prussia and Luise of Brunswick-Wolfenbüttel. Wilhelmina was the favorite niece of King Friedrich II of Prussia (Frederick the Great) and was the sister of his successor King Friedrich Wilhelm II of Prussia. The couple had three children who survived infancy including Willem I, the first King of the Netherlands.

When the Dutch Republic which Willem ruled was replaced by the Batavian Republic, Willem and his family fled to England where they lived in exile in the part of Kew Palace known as the Dutch House with the permission of Willem’s first cousin King George III. The family later went to Germany where they lived in Nassau and Brunswick. Willem spent the rest of his life in exile and was viewed quite negatively both in England and the Netherlands.

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Paternal First Cousins: Children of Princess Mary of Great Britain and Friedrich II, Landgrave of Hesse-Kassel

Prince Wilhelm of Hesse-Kassel (1741 – 1742), died in infancy

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Wilhelm I, Prince-Elector of Hesse (1743 – 1821)

When Wilhelm was four-years-old, his father Friedrich II, Landgrave of Hesse-Kassel deserted his family and converted to Roman Catholicism.  Along with his mother Mary of Great Britain and his two younger brothers, Wilhelm moved to Denmark where they lived with Mary’s sister, Louise of Great Britain who was Queen Consort of Denmark. Wilhelm married his first cousin Princess Caroline of Denmark, daughter of his maternal aunt Louise and her husband King Frederik V of Denmark, and had two daughters and two sons. Upon the death of his father, Wilhelm became Wilhelm IX, Landgrave of Hesse-Kassel. Later he was created Prince-Elector of Hesse.

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Prince Karl of Hesse-Kassel (1744 – 1836)

A younger brother of Wilhelm I, Prince-Elector of Hesse, Karl was brought up with relatives at the Danish court and spent most of his life in Denmark. Like his elder brother, he married also married a Danish first cousin, Princess Louise of Denmark, the youngest daughter of his maternal aunt, Princess Louise of Great Britain, and King Frederik V of Denmark. Karl and Louise had three sons and three daughters including Marie Sophie, who became Queen of Denmark by marrying her first cousin the future King Frederik VI of Denmark. Karl had a military career in the Danish Army and served as Governor-General of Norway and Royal Governor of Schleswig-Holstein.

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Prince Friedrich of Hesse-Kassel (1747 – 1837)

The youngest son of Princess Mary of Great Britain and Friedrich II, Landgrave of Hesse-Kassel, Friedrich was raised in Denmark and spent most of his life there. Like his brother Karl, Friedrich had a career in the Danish Army. He married Princess Caroline of Nassau-Usingen and had five sons and three daughters, including Wilhelm who married Princess Louise Charlotte of Denmark and was the father of Louise of Hesse-Kassel, wife of King Christian IX of Denmark. Friedrich bought Rumpenheim Castle, now in Offenbach, Germany, from his brother Karl, and it became his family’s seat. The large extended family of Friedrich’s granddaughter Louise of Hesse-Kassel and her husband King Christian IX of Denmark had many family get-togethers at Rumpenheim Castle.

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Paternal First Cousins: Children of Princess Louise of Great Britain and Frederik V, King of Denmark and Norway

Crown Prince Christian of Denmark (1745 – 1747), died in early childhood

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Princess Sophia Magdalena of Denmark, Queen of Sweden (1746 – 1813)

Princess Sophia Magdalena was the eldest daughter and the eldest surviving child of the four children of King Frederik V of Denmark and his first wife Princess Louisa of Great Britain. She married King Gustav III of Sweden and had two sons including King Gustav IV Adolf of Sweden. On March 16, 1792, Sophia Magdalena’s husband King Gustav III was shot by Jacob Johan Anckarström during a masquerade at the Royal Opera House. King Gustav III died of his wounds at the Stockholm Royal Palace two weeks later. The event is the subject of Giuseppe Verdi’s 1859 opera Un Ballo in Maschera (The Masked Ball).

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Princess Caroline of Denmark, Princess-Electress of Hesse (1747 – 1820)

Caroline of Denmark married her maternal first cousin Wilhelm I, Prince-Elector of Hesse and had two sons and two daughters. As explained above, Wilhelm grew up at the Danish court and it was decided during their childhood that they would marry each other. Shortly after their marriage, Caroline and Wilhelm left Denmark to live in Hanau, the capital of the County of Hanau-Münzenberg, which had been separated from Hesse-Kassel and given to Wilhelm. Upon the death of his father, Wilhelm became Wilhelm IX, Landgrave of Hesse-Kassel. Later he was created Prince-Elector of Hesse.

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King Christian VII of Denmark (1749 – 1808)

King Christian VII married his maternal first cousin Princess Caroline Matilda of Wales, the youngest sibling of King George III of the United Kingdom. They had one son, King Frederik VI of Denmark, and one daughter. King Christian VII’s reign was marked by mental illness. He publicly declared that he could not love Caroline Matilda because it was “unfashionable to love one’s wife”. Caroline Matilda’s daughter Louise Augusta’s father may have been Christian’s physician Johann Friedrich Struensee. Struensee gained political power and also gained powerful enemies, including Christian VII’s stepmother Queen Dowager Juliana Maria and her son Hereditary Prince Frederik. Juliana Maria directed a plot to overthrow the lovers, which ended with the brutal execution of Struensee and Caroline Matilda’s divorce and banishment. Not quite 20-years-old, Caroline Matilda lost her title of Queen and was forcibly separated from her children whom she never saw again. She died of “a putrid fever and sore throat,” probably scarlet fever, at the age of 23. Because of his mental illness, Christian was only nominally king from 1772 onward and regents ruled for him. Christian lived in isolation with a caretaker. His only involvement with the government was when he had to sign “Christian Rex” on formal papers.

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Princess Louise of Denmark, Princess of Hesse-Kassel (1750 – 1831)

Princess Louise married her maternal first cousin Prince Karl of Hesse-Kassel (see above) who had grown up with her at the Danish court. The couple had three daughters and three sons daughters including Marie Sophie, who became Queen of Denmark by marrying her first cousin the future King Frederik VI of Denmark.

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MATERNAL FIRST COUSINS

Maternal First Cousins: Children of Friedrich III, Duke of Saxe-Gotha-Altenburg and Luise Dorothea of Saxe-Meiningen

Hereditary Prince Friedrich Ludwig on the right and his tutor Baron Ulrich von Thun

Friedrich Ludwig, Hereditary Prince of Saxe-Gotha-Altenburg (1735 – 1756)

Friedrich Ludwig was very well-educated. Along with his tutor Baron Ulrich von Thun, he took a lengthy multi-year educational journey through Europe where he became acquainted with proponents of French Enlightenment such as Voltaire, Jean-Jacques Rousseau, and Denis Diderot. Friedrich Ludwig was often sick as a child and he died at the age of 21 after suffering from a fever and severe gouty pains. Friedrich Ludwig’s younger brother Ernst became Hereditary Prince and later Duke of Saxe-Gotha-Altenburg.

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Ludwig of Saxe-Gotha-Altenburg (born and died 1735)

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Friederike Luise of Saxe-Gotha-Altenburg (1741 – 1776)

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Ernst II, Duke of Saxe-Gotha-Altenburg (1745 – 1804)

After the death of her eldest son, Ernst’s mother Luise Dorothea of Saxe-Meiningen was intent that her two surviving sons be well educated. They were carefully educated by select tutors and went on an educational trip to the Netherlands, England, and France where they met important people in politics, science and the arts. When he became Duke of Saxe-Gotha-Altenburg, Ernst continued his interest in the arts and science in his duchy. Ernst married Princess Charlotte of Saxe-Meiningen and had four sons, two of them became Dukes of Saxe-Gotha-Altenburg. Their son August, Duke of Saxe-Gotha-Altenburg married his first cousin Luise Charlotte of Mecklenburg-Schwerin and their daughter Louise was the mother of Prince Albert of Saxe-Coburg and Gotha, the husband of Queen Victoria and the ancestor of all British monarchs beginning with Edward VII, and of numerous other European monarchs.

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Sophie of Saxe-Gotha-Altenburg (born and died 1746)

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August of Saxe-Gotha-Altenburg (1747 – 1806)

August was carefully educated with his brother Ernst as explained above. He was to have a career in the military but that did not last long. August never married and was considered a prince of the Enlightenment. He was an important translator of French literature and corresponded with several important German writers including Johann Wolfgang von Goethe.

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Maternal First Cousins: Children of Johann August of Saxe-Gotha-Altenburg and Louise Reuss of Schleiz, co-Countess of Limpurg-Gaildorf

Augusta Luise Friederike of Saxe-Gotha-Altenburg, co-Countess of Limpurg-Gaildorf, Princess of Schwarzburg-Rudolstadt (1752 – 1805)

Upon the death of her mother, Augusta and her sister Luise inherited the title of Co-Countess of Limpurg-Gaildorf. Later the sisters sold their shares of Limpurg-Gaildorf to Carl Eugen, Duke of Württemberg. Augusta became the second wife of Friedrich Karl, Prince of Schwarzburg-Rudolstadt but the marriage was childless.

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Luise of Saxe-Gotha-Altenburg, Co-Countess of Limpurg-Gaildorf, Duchess of Mecklenburg-Schwerin (1756 – 1808)

As explained above, Luise became co-Countess of Limpurg-Gaildorf with her sister Augusta upon the death of their mother and the sisters later sold their portion of the County of Limpurg-Gaildorf. Luise married Friedrich Franz I, Duke of Mecklenburg-Schwerin, who became the first Grand Duke of Mecklenburg-Schwerin after Luise’s death. Luise and Friedrich Franz had four sons and two daughters. Their daughter Charlotte Frederica was the first wife of the future King Christian VIII of Denmark and the mother of King Frederik VII of Denmark. Charlotte Frederica’s marriage was unhappy and she and her husband eventually divorced.

Luise Charlotte, another daughter of Luise and Friedrich Franz, married August, Duke of Saxe-Gotha-Altenburg and their daughter Luise was the mother of Prince Albert of Saxe-Coburg and Gotha, the husband of Queen Victoria and the ancestor of all British monarchs beginning with King Edward VII and of numerous other European monarchs.

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Maternal First Cousins: Children of Friederike of Saxe-Gotha-Altenburg and Johann Adolf II, Duke of Saxe-Weissenfels

All their children died in childhood.

  • Karl Frederick Adolf, Hereditary Prince of Saxe-Weissenfels (1736 – 1737)
  • Johann Adolf, Hereditary Prince of Saxe-Weissenfels (born and died 1738)
  • August Adolf, Hereditary Prince of Saxe-Weissenfels (1739 – 1740)
  • Johann Georg Adolf, Hereditary Prince of Saxe-Weissenfels (born and died 1740)
  • Friederike Adolfine of Saxe-Weissenfels (1741 – 1751)

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Maternal First Cousins: Children of Johann Adolf of Saxe-Gotha-Altenburg and his morganatic wife Marie Maximiliane Elisabeth Schauer

Marie Maximiliane Elisabeth Schauer and her two surviving children were ennobled by Joseph II, Holy Roman Emperor and given permission to discard the surname Schauer and instead use the surname von Gothart

  • Friedrich Adolph (born and died 1760)
  • Adolph Christian Carl von Gothart (1761 – 1835)
  • Johanna Adolfine Friederike von Gothart (1767 – 1804)

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Works Cited

  • Lundy, D. (2019). Main Page. [online] Thepeerage.com. Available at: http://www.thepeerage.com/. (for genealogy information)
  • Unofficial Royalty. (2019). Unofficial Royalty. [online] Available at: https://www.unofficialroyalty.com. (for biographical and genealogy information)
  • Wikipedia. (2019). Main Page. [online] Available at: https://en.wikipedia.org/.  (for biographical and genealogy information)