George IV ( born as George Augustus Frederick on 12 August 1762 , died on 26 June 1830 ) was king of the United Kingdom of Great Britain and Ireland and Hanover from 29 January 1820 until his death . George IV ( George Augustus Frederick ; 12 August 1762 â `` 26 June 1830 ) was the King of the United Kingdom of Great Britain and Ireland and also of Hanover from the death of his father , George III , on 29 January 1820 until his own death ten years later .