Unfortunately it’s highly unlikely that horned horses ever roamed the Earth
No reliable evidence has ever been found that suggests they existed, and it’s much more likely that the rumour started from garbled accounts of rhinoceroses
An ancient Greek doctor named Ctesias wrote of a one-horned wild ass he had heard about from other travellers in the fourth century. Both Marco Polo and Genghis Khan reported having seen unicorns, with Kahn allegedly refusing to invade India because of the fearsome creatures. The animals had a single horn and were described as ‘ugly brutes’ that were ‘as large as horses.’
Scientists now think that these unicorn sightings were probably sightings of rhinos, and the theory is so widely accepted that the Indian rhino’s Latin name is Rhinoceros unicornis.
In times before modern technology arose, few people were able to explore new lands and those that depicted strange animals in artwork had usually only heard descriptions of them. Upon hearing tales of one-horned beasts the size of horses, an artist may have produced works resembling what we now recognise to be unicorns.