In 1283, when he lay ailing in Sevilla, his last loyal city, Alfonso X el Sabio had his writers and artists compile the last great book of his reign. Gathering information from the best sources, the Book of Chess is the definitive work on the subject for its time. Like other books commissioned by Alfonso, this one also adds new material. In a new game called "Grant Açedrex" new strange and wondrous pieces in the shapes of animals are introduced and described. Can you guess what the Unicorn piece really represented?
E ell Vnicornio es bestia muy grant & muy fuerte. & ha dos cuernos ell vno en la fruente & ell otro en la nariz. & el dela nariz es mas luengo que el dela fruente. & ha tan grand ualentia en el cuerno dela nariz quel mete al marfil por el uientre & alçalo de tierra. & de el cuerno dela fruente es agudo. & taia muy fuerte. & este Unicornio ael cuerpo grant como marfil & la color como de ceniza. & las piernas tales como el marfil. E las oreias commo de puerco & quando es sannudo paransele los oios bermeios como el rubi... (Text from http://history.chess.free.fr/acedrex.htm)
The Unicorn is a very large and very strong beast with two horns – one on its forehead and one on its nose. The one on its nose is longer than the one of its forehead and is so strong that it spears an elephant in the gut and lifts it from the ground. The forehead horn is sharp and cuts powerfully. This Unicorn is as large as an elephant and ash colored. It has legs like an elephant and ears like a pig, and when it is angry, its eyes turn as red as ruby.
Apparently, it is common to talk about unicorns as huge grey beasts with pig ears in the thirteenth century. Marco Polo would have seen Asian rhinoceroses, or at least representations of them, and appropriately called them "one-horns." The problem comes when trying to apply such a name to the double-horned African rhinos so many other travelers to southern Europe would have been familiar with.