When the colonizers came, the natives tried to fight.
When they lost, they fled.
And when the colonizers pursued, the natives fled further. They opened the holes between dreams and moved into the unseen world.
The dreams tried to fight, and lost, and fled in their turn.
Now the natives have made the unseen world their home. They have changed and developed and few see anything of value in the seen world.
Until one of them discovers the internet.
Or, if that last line is too stupid for you:
“…until a party of explorers stumble into the unseen world. They say they were sent by a man named ‘Thomas Jefferson’…”
Maybe those “dreams” are just Australopithecines in a world where humans never evolved.