claim: George III was killed by his son.
evidence: George III -LRB- George William Frederick ; 4 June 1738 -- 29 January 1820 -RRB- was King of Great Britain and Ireland from 25 October 1760 until the union of the two countries on 1 January 1801 , after which he was King of the United Kingdom of Great Britain and Ireland until his death .. King of Great Britain and Ireland. List of British monarchs. King. List of British monarchs. Great Britain. Kingdom of Great Britain. Ireland. Kingdom of Ireland. the union of the two countries. Acts of Union 1800. United Kingdom of Great Britain and Ireland. United Kingdom of Great Britain and Ireland. He was concurrently Duke and prince-elector of Brunswick-Luneburg -LRB- `` Hanover '' -RRB- in the Holy Roman Empire until his promotion to King of Hanover on 12 October 1814 .. Hanover. House of Hanover. King. List of British monarchs. prince-elector. prince-elector. Holy Roman Empire. Holy Roman Empire. King of Hanover. Kingdom of Hanover. He was the third British monarch of the House of Hanover , but unlike his two predecessors he was born in Britain , spoke English as his first language , and never visited Hanover .. Hanover. House of Hanover. House of Hanover. House of Hanover. His life and with it his reign , which were longer than any other British monarch before him , 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 .. Great Britain. Kingdom of Great Britain. However , many of Britain 's American colonies were soon lost in the American War of Independence .. American War of Independence. American Revolutionary War. Further wars against revolutionary and Napoleonic France from 1793 concluded in the defeat of Napoleon at the Battle of Waterloo in 1815 .. revolutionary. French Revolution. Napoleonic France. First French Empire. Napoleon. Napoleon. Battle of Waterloo. Battle of Waterloo. In the later part of his life , George III had recurrent , and eventually permanent , mental illness .. mental illness. Mental disorder. Although it has since been suggested that he had the blood disease porphyria , the cause of his illness remains unknown .. porphyria. porphyria. After a final relapse in 1810 , a regency was established , and George III 's eldest son , George , Prince of Wales , ruled as Prince Regent .. regency. Regency era. Prince Regent. Prince Regent. On George III 's death , the Prince Regent succeeded his father as George IV .. George IV. George IV of the United Kingdom. Prince Regent. Prince Regent. 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 .. Until it was reassessed in the second half of the 20th century , his reputation in the United States was one of a tyrant ; and in Britain he became `` the scapegoat for the failure of imperialism '' .