William was born at Buckingham Palace in London on 21 August 1765.
He was the third son of George III and Queen Charlotte and as such was not expected to succeed to the throne.
From the early 1790s until 1811, William lived with his mistress, the actress Dorothy Jordan. They had 10 children who took the surname Fitzclarence. It is suggested that the current Prime Minister David Cameron is a descendant from this relationship.
In 1811, William’s oldest brother George became prince regent (later George IV) when their father was declared insane.
The death of the prince regent’s only daughter in 1818 resulted in a scramble among George’s brothers to marry and produce heirs.
William married Princess Adelaide of Saxe-Meiningen in 1818.
With the death of George III’s second son, William became heir and then, with the death of George IV, king in June 1830.
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