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Politics & World • Monarchy

King George III

George III (George William Frederick) was King of Great Britain and Ireland from 1760 to 1801, and then King of the United Kingdom of Great Britain and Ireland from 1801 until his death in 1820.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

George III (George William Frederick) was King of Great Britain and Ireland from 1760 to 1801, and then King of the United Kingdom of Great Britain and Ireland from 1801 until his death in 1820. He was also Elector, and later King, of Hanover. His long reign is closely associated with the loss of the American colonies, the Acts of Union 1800, and the Regency period after his illness.

Early life and accession

George III was born in 1738 in London and was the eldest son of Frederick, Prince of Wales, and Princess Augusta of Saxe-Gotha. He became heir apparent in 1751 and succeeded George II in 1760.

Reign over Great Britain and Ireland

George III ruled during major imperial and constitutional change, including the American Revolutionary War and the loss of the Thirteen Colonies. He was monarch when Great Britain and Ireland were united into the United Kingdom in 1801.

Hanover and continental Europe

In addition to the British crown, George III was Elector of Hanover from 1760 to 1814 and King of Hanover from 1814 to 1820. His reign overlapped with the Seven Years' War and the Napoleonic era in Europe.

Illness and Regency

George III experienced recurring periods of serious illness late in life. From 1811, his eldest son governed as Prince Regent until George III's death in 1820.

Key facts

  • George III was born in London and became king in 1760 after the death of his grandfather, George II.
  • He reigned for almost 60 years, among the longest reigns in British history.
  • During his reign, Great Britain lost its American colonies after the American Revolutionary War.
  • The Acts of Union 1800 united Great Britain and Ireland into the United Kingdom in 1801.
  • His later years were marked by recurrent illness, and his son served as Prince Regent from 1811.
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Canadian context

George III was monarch during the period when Britain expanded and reorganized its North American colonies, shaping the imperial context that later influenced the territory that became Canada.

Frequently asked questions

Who was King George III?
George III was the King of Great Britain and Ireland, later King of the United Kingdom of Great Britain and Ireland, from 1760 to 1820.
Why is George III historically significant?
He ruled during the American Revolution, the loss of the American colonies, and the creation of the United Kingdom in 1801.
Was George III king of Hanover too?
Yes. He was Elector of Hanover from 1760 to 1814 and King of Hanover from 1814 until his death.
How long did George III reign?
He reigned for almost 60 years, one of the longest reigns in British history.
What happened near the end of his reign?
After recurring illness, his son acted as Prince Regent from 1811, and George III died in 1820.

References

  1. Britannica — https://www.britannica.com/biography/George-III
    Supports: Birth, death, reign dates, titles, and historical significance.
  2. The Royal Family — https://www.royal.uk/george-iii
    Supports: Birth, accession, Hanoverian status, illness, regency, death, and reign length.
  3. Library of Virginia — https://www.lva.virginia.gov/collections/educator-resources/online-classroom/stc/people/george-iii-(1738-1820)
    Supports: King of Great Britain, birth, death, and burial information.