Favourable reviews of Kevin MacDonald's newly released film The Eagle are spinning over into renewed sales of the book on which it is based, Rosemary Sutcliff's 1954 children's classic The Eagle of the Ninth. Still in print more than 50 years on, The Eagle of the Ninth is the first of a series of novels in which Sutcliff, who died in 1992, explored the cultural borderlands between the Roman and the British worlds – "a place where two worlds met without mingling" as she describes the British town to which Marcus, the novel's central character, is posted. Marcus is a typical Sutcliff hero, a dutiful Roman who is increasingly drawn to the British world of "other scents and sights and sounds; pale and changeful northern skies and the green plover calling". This existential cultural conflict gets even stronger in later books like The Lantern Bearers and Dawn Wind, set after the fall of Rome, and has modern resonance. But Sutcliff was not just a one-trick writer. The range of her novels spans from the Bronze Age and Norman England to the Napoleonic wars. Two of her best, The Rider of the White Horse and Simon, are set in the 17th century and are marked by Sutcliff's unusually sympathetic (for English historical novelists of her era) treatment of Cromwell and the parliamentary cause. Sutcliff's finest books find liberal-minded members of elites wrestling with uncomfortable epochal changes. From Marcus Aquila to Simon Carey, one senses, they might even have been Guardian readers.