When did I first find out about Unicorns? In a book, probably. Something about myths and legends. Always a white horse with a horn from its forehead. The closest thing in reality in nature are Narwhals, a type of cetacean with a long modified tooth sticking out forward from its head.
Unicorns are often depicted in medieval paintings, tapestries and manuscripts. Apparently the only way you could catch them was to have them lay their head in the lap of a virgin? They were a lovely idea. Perhaps the idea was influenced by antelope? It’s something I might investigate.