Original: William Henry Cavendish-Bentinck , 3rd Duke of Portland , KG , PC ( 14 April 1738 â '' 30 October 1809 ) was a British Whig and Tory statesman , Chancellor of the University of Oxford and Prime Minister .
Simplified: William Henry Cavendish Cavendish-Bentinck , 3rd Duke of Portland , ( 14 April 1738 â '' 30 October 1809 ) was a British Whig and Tory statesman and Prime Minister of Great Britain .