He reconstructs the extraordinary financial history of the dukes of Devonshire, narrates the story of the Cozens-Hardys, a Norfolk family who played a remarkably varied part in the life of their county, and offers a controversial reappraisal of the forebears, lives, work, and personalities of Harold Nicolson and Vita Sackville-West - a portrait, notes Cannadine, of more than a marriage.