The first written description of a unicorn is attributed to a fifth century Greek. However, all alleged skeletal remains, including some discovered in the 17th century, have been proved fakes.
In medieval times, the mythical creatures were used as symbols for Christ, purity, chastity, power and royalty. Many people of the time believed that the unicorn could be captured by a virginal maiden and that its horn could purify water. Some churches added fragments of the supposed horns to their holy water, but these were actually pieces from the horn-shaped teeth of narwhals. Still, English and Austrian royalty added intact specimens of the horns to their scepters, and King Frederick the Third of Denmark used the material in the construction of his throne.
Some scholars believe that the European myths grew out of tales of an actual Eurasian rhinoceros that had earlier became extinct. Thirteenth century explorer Marco Polo made such a mistake, falsely identifying a Javan rhino as a unicorn in his travelogues. The King James Bible also misidentified the beasts, referencing the unicorn nine times, where later translators substituted "ox".
As in the case of the Prato Unicorn, sighted in Italy in 2008, the horns of deer, cattle and goats sometimes do grow together into a single, unicorn-like shape. Some blame 20th-century sightings on this type of occurrence.