The Romance of Alexander is an account of the adventures of Alexander the Great. It is attributed to Callisthenes, Alexander’s court historian. The historical Callisthenes died in 327 BC, four years before Alexander, so he could not have written the chapters on the final four years of Alexander’s life. The book’s unnamed author is called Pseudo-Callisthenes.
Genghis Khan and Alexander were separated by 1500 years, but the Romance of Alexander was the first Western book to be translated into Mongolian. In the book’s Mongolian version, when Alexander becomes a great conqueror, he says: “I have become Great Khan. On this very earth there has not been born a Khan who has enjoyed life as I.” The Mongolian version of the book ends with these lines: “It is over, is ended, ended!”
Genghis Khan’s biography, The Secret History, contains several references to Alexander. According to the book, in Afghanistan Alexander killed a unicorn, which is a sacred creature. Due to the curse of killing a sacred unicorn, he soon died. Marco Polo, who worked in the Chinese court of Genghis Khan’s grandson Kublai Khan, has claimed that Alexander’s horse Bucephalus bred with a unicorn to produce a new breed of horse with a mark on its forehead.
According to some Mongol chroniclers, Monge Khan, Genghis Khan's grandson who became the Great Khan in 1251, used to examine the Mongolian version of the Romance of Alexander to discover insights for administering his Mongol empire.