'William Pitt', (1881). British statesman William Pitt the Younger (1759-1806) became Prime Minister at the age of 24, making him the youngest to hold the office in British history. He was also one of the longest serving Prime Ministers, holding office from 1783-1801 and then again from 1804-1806. From Old and New London: A Narrative of Its History, Its People, and Its Places. Westminster and the Western Suburbs, by Edward Walford, Vol. III. [Cassell, Petter, Galpin & Co., London, Paris & New York, 1881]