Having read Lionheart and Lackland, Frank McLynn’s enthralling twin biography of Richard the Lionheart and his younger brother John, I was looking forward to his life of the world’s greatest ever conqueror, Genghis Khan. But while McLynn brought Richard and John and a cast of other characters (particularly the psychotic troubadour Bertran de Born) vividly to life in Lionheart and Lackland, he never achieves the same synthesis of historical scholarship and storytelling verve in this book. Genghis Khan and his band of generals remain obstinately stuck on the page rather than entering the reader’s imagination: ciphers with an astonishing propensity to slaughter vast numbers of people. Maybe the problem is the one Hannah Arendt identified: evil tends to banality, and after slaughtering the inhabitants of yet another city for having the temerity to resist the Mongol onslaught, it all becomes, for the reader, a little tedious. Also, given the vast areas conquered and the part that rapid rides across difficult geographies played in the Mongol conquest, the book’s allergy to maps is really rather puzzling. Many a page describing how the horde rode here, there and on could have been rendered superfluous and more understandable with a map. Still, the book is a solid overview of the conquests of the Khan and his immediate descendants.