I was reading up on mythology for my mermaid hub and i found this piece about Unicorns.........The Romans were very familiar with rhinos because they used them in their Roman games at the Coliseum. Then Africa became cut off from Europe with the fall of the Roman Empire and the rise of the Ottoman Empire. With Europeans being no longer able to travel to central Africa, knowledge about the rhinoceros became hazy. Eventually the only thing that Europeans knew about it was a description that it was a horse like creature with a horn in the middle of its forehead. Artists in Europe, who had never seen a rhinoceros, drew it exactly like this, not knowing that it had a far heavier build than any horse. Then because of its unusual appearance as depicted by the artists, it became a popular mythological and magical creature.
This myth was made more confusing in the Middle Ages, when whalers began to hunt for Narwhals. These are medium size whales about 5m long. The males have a long spiral tusk growing out of their forehead. These horns were so unusual that con men began to sell them as unicorn horns. This is why in many pictures of unicorns they have spiral horns. It seems these con men, in order to make these horns “a must have item”, they claimed that unicorn horns were a protection against poisoning. It seems they completely fooled the aristocratic class, because it became fashionable to put parts of these horns in their drinks, thinking they were magical unicorn horns that would nullify the effects of any poison. Pharmacies at the time called these horns alicorn and they were widely used up until the mid 18th century in medicines.
This myth making changed the perception of the unicorn so much, that when Europeans moved back to Africa, sailing there by ship and seeing rhinos, they no longer recognised them as unicorns and renamed them.