George III (George William Frederick; June 4, 1738 – January 29, 1820) was King of Great Britain and King of Ireland from his accession on October 25, 1760 until the union of the two countries on January 1, 1801, after which he was King of the United Kingdom of Great Britain and Ireland until his death in 1820. He was concurrently Duke and Prince-Elector of Brunswick-Lüneburg (“Hanover”) in the Holy Roman Empire before becoming King of Hanover on October 12, 1814. He was a monarch of the House of Hanover, but unlike his two predecessors, he was born in Great Britain, spoke English as his first language, and never visited Hanover.

George III, King of the United King of Great Britain and Ireland. King of Hanover
Family
George was born in London at Norfolk House in St James’s Square. As he was born two months prematurely and thought unlikely to survive, he was baptised the same day by Thomas Secker, who was both Rector of St James’s and Bishop of Oxford. One month later, he was publicly baptised at Norfolk House, again by Secker. His godparents were King Friedrich I of Sweden (for whom Lord Baltimore stood proxy), his uncle Friedrich III, Duke of Saxe-Gotha (for whom Lord Carnarvon stood proxy), and his great-aunt Sophia-Dorothea, Queen in Prussia (for whom Lady Charlotte Edwin stood proxy).

George II, King of Great Britain and Ireland.
George III was the grandson of King George II, and the eldest son of Frederick-Louis, Prince of Wales, and Augusta of Saxe-Gotha.
George III’s father was Frederick-Louis, Prince of Wales, (1707-1751), was heir apparent to the British throne from 1727 until his death from a lung injury at the age of 44. He was the eldest but estranged son of King George II and Caroline of Ansbach.
Under the Act of Settlement passed by the English Parliament in 1701, Frederick-Louis was fourth in the line of succession to the British throne at birth, after his great-grandmother (Electress Sophia of Hanover) paternal grandfather (George I) and father (George II). He moved to Great Britain following the accession of his father, and was created Prince of Wales. He predeceased his father, however, and upon the latter’s death on October 25, 1760, the throne passed to Prince Frederick’s eldest son, George III.

Frederick-Louis, Prince of Wales (Father)
George III’s mother, Princess Augusta of Saxe-Gotha-Altenburg was born in Gotha to Friedrich II, Duke of Saxe-Gotha-Altenburg (1676–1732) and Magdalena Augusta of Anhalt-Zerbst (1679–1740). Her paternal grandparents were Friedrich I, Duke of Saxe-Gotha-Altenburg and Magdalena-Sibylla of Saxe-Weissenfels, a daughter of August, Duke of Saxe-Weissenfels, and his wife Anna-Maria of Mecklenburg-Schwerin. Magdalena-Sibylla’snpaternal grandparents were Johann-Georg I, Elector of Saxony, and Magdalene Sibylle of Prussia.

Princess Augusta of Saxe-Gotha-Altenburg (Mother)
Friedrich I, Duke of Saxe-Gotha-Altenburg, was the eldest surviving son of Ernst I, Duke of Saxe-Gotha-Altenburg and his cousin Elisabeth-Sophie of Saxe-Altenburg.
Princess Augusta did not speak French or English, and it was suggested that she be given lessons before the wedding, but her mother did not consider it necessary as the British royal family were from Germany (Holy Roman Empire). She arrived in Britain, speaking virtually no English, for a wedding ceremony with Frederick-Louis, Prince of Wales, which took place almost immediately, on May 8,1736, at the Chapel Royal in St James’s Palace, London.
Although he was the first British King of the House of Hanover born in England with English his native language, the ancestry of George III was thoroughly German.
Marriage
In 1759, George was smitten with Lady Sarah Lennox, sister of Charles Lennox, 3rd Duke of Richmond, but Lord Bute advised against the match and George abandoned his thoughts of marriage. “I am born for the happiness or misery of a great nation,” he wrote, “and consequently must often act contrary to my passions.” The prominent Lennox Family of Richmond were illegitimate descendants of King Charles II of England.

Lady Sarah Lennox
In 1753 attempts were made by King George II to marry his grandson George, Prince of Wales to Princess Sophie-Caroline of Brunswick-Wolfenbüttel, eldest daughter of Charles I, Duke of Brunswick-Wolfenbüttel, and his wife, Philippine-Charlotte of Prussia, sister of Friedrich II the Great of Prussia.
This was an attempt to improve relations with Prussia, as Sophie-Caroline was a niece of Friedrich II of Prussia and George II needed Prussian troops to help offset the alliance between France and Austria that had occurred as a result of the Diplomatic Revolution. Prince George’s mother, Augusta, Dowager Princess of Wales, thwarted George II’s plans, however, which increased tensions within the British royal family. Sophie-Caroline married Friedrich, Margrave of Bayreuth, instead.

Princess Sophie-Caroline of Brunswick-Wolfenbüttel
Though this match was not to be, Sophie-Caroline’s brother Charles II, Duke of Brunswick-Wolfenbüttel, married George’s sister Princess Augusta in 1764, and George III’s son George IV married their daughter Caroline of Brunswick, thus continuing the close ties between the two houses.
The following year, at the age of 22, George succeeded to the throne when his grandfather, George II, died suddenly on 25 October 25, 1760, two weeks before his 77th birthday. The search for a suitable wife intensified. On September 8, 1761 in the Chapel Royal, St James’s Palace, the King married Princess Charlotte of Mecklenburg-Strelitz, whom he met on their wedding day.

Princess Charlotte of Mecklenburg-Strelitz
Princess Charlotte of Mecklenburg-Strelitz was the youngest daughter of Duke Charles-Ludwig-Friedrich of Mecklenburg (1708–1752; known as “Prince of Mirow”) and of his wife Princess Elisabeth-Albertine of Saxe-Hildburghausen (1713–1761). Mecklenburg-Strelitz was a small north-German duchy in the Holy Roman Empire.

Young George III
A fortnight after the wedding on September22, both were crowned at Westminster Abbey. George remarkably never took a mistress (in contrast with his grandfather and his sons), and the couple enjoyed a genuinely happy marriage until his mental illness struck.
They had 15 children—nine sons and six daughters. In 1762, George purchased Buckingham House (on the site now occupied by Buckingham Palace) for use as a family retreat. His other residences were Kew Palace and Windsor Castle. St James’s Palace was retained for official use. He did not travel extensively and spent his entire life in southern England. In the 1790s, the King and his family took holidays at Weymouth, Dorset, which he thus popularised as one of the first seaside resorts in England.
George III’s life and reign, at 59 years, which was longer than those of any of his predecessors at the time, were marked by a series of military conflicts involving his kingdoms, much of the rest of Europe, and places farther afield in Africa, the Americas, and Asia. Early in his reign, Great Britain defeated France in the Seven Years’ War, becoming the dominant European power in North America and India. However, many of Britain’s American colonies were soon lost in the American War of Independence. Further wars against revolutionary and Napoleonic France from 1793 concluded in the defeat of Napoleon at the Battle of Waterloo in 1815.

George III, King of the United Kingdom of Great Britain and Ireland, King of Hanover
In the later part of his life, George had recurrent, and eventually permanent, mental illness. Although it has since been suggested that he had bipolar disorder or the blood disease porphyria, the cause of his illness remains unknown. After a final relapse in 1810, a regency was established. His eldest son, George, Prince of Wales, ruled as Prince Regent until his father’s death, when he succeeded as George IV. Historical analysis of George III’s life has gone through a “kaleidoscope of changing views” that have depended heavily on the prejudices of his biographers and the sources available to them.
Changing Titles.
The nation went through many changes through his reign and his titles reflected these changes.
In Great Britain, George III used the official style “George the Third, by the Grace of God, King of Great Britain, France, and Ireland, Defender of the Faith, and so forth”. In 1801, when Great Britain united with Ireland, he dropped the title of King of France, which had been used for every English monarch since Edward III’s claim to the French throne in the medieval period. His style became “George the Third, by the Grace of God, King of the United Kingdom of Great Britain and Ireland, Defender of the Faith.”
In Germany, he was “Duke of Brunswick and Lüneburg, Arch-Treasurer and Prince-Elector of Hanover of the Holy Roman Empire” (Herzog von Braunschweig und Lüneburg, Erzschatzmeister und Kurfürst des Heiligen Römischen Reiches) until the end of the empire in 1806. He then continued as Duke until the Congress of Vienna declared him “King of Hanover” in 1814.