Henry Addington , 1st Viscount Sidmouth , PC ( 30 May 1757 â `` 15 February 1844 ) was a British statesman . He was Prime Minister of the United Kingdom from 1801 to 1804 . Henry Addington , 1st Viscount Sidmouth , PC ( 30 May 1757 -- 15 February 1844 ) was a British statesman , and Prime Minister of the United Kingdom from 1801 to 1804 .