In fifteenth-century Eastern Europe, Vlad III of Wallachia conducted a reign of terror. He had citizens impaled by the thousands. People were butchered on his merest whim. In his realm, and beyond it, men and women lived in dread of the Impaler Prince. And this Prince revelled in the horror he inspired. He was a sadist, seen by some as a being of unequalled depravity, even as the Devil's own spawn. But Vlad was also a man who had the qualities of...