Original: - 29 January 1820 [N.S.]) was King of Great Britain and King of Ireland from 25 October 1760 until the union of these two countries on 1 January 1801, after which he was King of the United Kingdom of Great Britain and Ireland until his death.
Simplified: George III (Born George William Frederick June 4, 1738 - January 29, 1820) was King of Great Britain and King of Ireland from October 25, 1760 until January 1, 1801.