London: George G. Harrap & Co. Ltd, 1933-38. First edition of Churchill's magisterial biography of his notable ancestor John Churchill, 1st Duke of Marlborough. Octavo, 4 volumes, original cloth, top edge gilt, illustrated with hundreds of maps and plans (many folding), plates and document facsimiles. Association copy, inscribed by Winston Churchill on the front free endpaper of volume IV, "To Maurice Ashley from Winston Churchill August 1938." The recipient, Maurice Ashley worked as a research assistant to Winston Churchill for four years during which he was working on the Marlborough biography. Ashley is also the author of Churchill as Historian (1968), which discusses how Churchill approached historical research. Each volume is very good in a very good dust jacket. Vol. I with a price-clipped dust jacket. An exceptional example. John Churchill, the Duke of Marlborough (1644-1722), was one of the greatest military commanders and statesmen in the history of England. Victorious in…