George III (George William Frederick; 4 June 1738 – 29 January 1820) was King of Great Britain and of Ireland from 25 October 1760 until his death in 1820. The two kingdoms were in a personal union under him until the Acts of Union 1800 merged them on 1 January 1801. He then became King of the United Kingdom of Great Britain and Ireland. He was concurrently Duke and Prince-elector of Brunswick-Lüneburg ("Hanover") in the Holy Roman Empire before becoming King of Hanover on 12 October 1814. He was a monarch of the House of Hanover who, unlike his two predecessors, was born in Great Britain, spoke English as his first language,[1] and never visited Hanover.[2]