John Patrick William Ehrman FBA (17 March 1920 – 15 June 2011) was a British historian, most notable for his three-volume biography of William Pitt the Younger. Boyd Hilton has claimed that "Pitt dominated the politics of his time and John Ehrman's three-volumes...dominate the historiography. It is hardly a biography, and indeed it is not clear that Pitt had an inner life to biographize, but it is a consummate account of the political ‘life and times’. The author's determination to deal with every episode in detail sometimes blurs the perspective, but readers can be assured that each topic has been thoroughly researched and that Ehrman's analysis is invariably judicious".