In this revisionist biography, Weatherford refurbishes the popular image of the great Mongol leader Genghis Khan, portraying him not just as a tyrant but also a religiously tolerant family man and entrepreneur on a world scale (not to mention military genius and crack administrator). The book is a lively portrait of Genghis Khan and the world of the Medieval Mongols, who once ruled the largest land empire on Earth. Weatherford, who has lived and studied in Mongolia, interweaves his own travels and field work on the Central Asian steppes, much of it on horseback. Professor Weatherford is a cultural anthropologist who teaches at Macalester College in St. Paul.  (CAS106, $14.95)