In terms of social organization and technology, it seems to me that Mesolithic Europeans (around 10,000 years ago) were like archaic Amerindians before agriculture. Many Amerindians on the west coast were still like that when Europeans arrived – foragers with bows and dugout canoes.
On the other hand, the farmers of Old Europe were in important ways a lot like English settlers: the pioneers planted wheat, raised pigs and cows and sheep, hunted deer, expanded and pushed aside the previous peoples, without much intermarriage. Sure, Anglo pioneers were literate, had guns and iron, were part of a state, all of which gave them a much bigger edge over the Amerindians than Old Europe ever had over the Mesolithic hunter-gatherers and made the replacement about ten times faster – but in some ways it was similar. Some of this similarity was the product of historical accidents: the local Amerindians were thin on the ground, like Europe’s Mesolithic hunters – but not so much because farming hadn’t arrived (it had in most of the United States), more because of an ongoing population crash from European diseases.
On the gripping hand, the Indo-Europeans seem to have been something like the Plains Indians: sure, they raised cattle rather than living off abundant wild buffalo, but they too were transformed into troublemakers by the advent of the horse. Both still did a bit of farming. They were also alike in that neither of them really knew what they were doing: neither were the perfected product of thousands of years of horse nomadry. The Indo-Europeans were the first raiders on horseback, and the Plains Indians had only been at it for a century, without any opportunity to learn state-of-the-art tricks from Eurasian horse nomads.
The biggest difference is that the Indo-Europeans won, while the Plains Indians were corralled into crappy reservations.
It turns out that all those Amerindians shared a fair amount of ancestry with the original Indo-Europeans (ANE, Sibermen), but that’s probably part of some cosmic joke for which we are the punchline.