So, there are quite a few depictions of what I’d loosely describe as ‘aliens’ in cave art, some of them are pretty ancient.
Sego Canyon Utah, 7,500 BP.
From Tassili, 8,000 BP.
Val Comonica, Italy, c. 12,000 BP. Kiev ‘alien’ figure, 6,000 BP. This is the most convincing one, in my opinion.
Wandjina’s from Australian cave art. These are meant to be spirits that bring rain. They are meant to be about the same size as children (Greys?).
Legends about the Wandjina say that they once caused a great flood that devastated the landscape and wiped out the human race. Disappointed with the corrupt behavior of humans, the Wandjina opened their mouths and released a torrent of water (Sounds familiar).
After the flood, the Wandjina spread out to different parts of the land. They created new humans and helped them set up a new society. To prevent further floods, the Wandjina kept their mouths closed. In time, their mouths disappeared completely.
There are quite a few medieval depictions, I’ll do them in another entry.