>What did the ancients make of the unpolluted night sky?
No idea and wouldn't like to even speculate.
The Egyptians had a Hippo constellation that has never been recognised and some cultures use the spaces in the Milky Way to make shapes which they named.
What is obvious to everyone in the northen hemisphere is that Orion is very prominent in winter and dissaperas for around 70 days.
Its return/dissapearance may have been marked in some way.