One of the things I find fascinating about Erich von Daniken is that he's never found any evidence of alien intervention in ancient Greece, Rome, or pre-celtic Europe. No, the ancient alien astronauts always intervene in the cultures of North and South America, Asia and Africa. Why? Do the ancient astronauts hate white people? I'm starting to suspect the aliens were trying to prevent the culture of Europe from escaping that one little corner of Asia they'd managed to confine it to.
European culture as the social equivalent of the cane toad/carp/rabbit invasions. "Damn it, Gurax, I thought you said there was no way those white people could escape where we had them penned in! You promised me the vastly superior cultures of the Middle East and Asia had more advanced mathematics, larger and more powerful boats, and that something called the 'Black Death' was ravaging Europe! What happened?"
"Dude, I have no idea. I swear, they were stewing in their own juices. They had a war that lasted a hundred fucking years! A hundred years of war! Who saw this whole 'sailing to another land, spreading disease and conquering the survivors' thing coming? I mean, we uplifted EVERY OTHER CULTURE! I was not ready for this!"
In other words, von Daniken is full of crap, but it's amusing to imagine European civilization as something alien xenozoologists tried to keep penned up.