1491. Never was a book so aptly named. Just like there was a pre- and a post- 9/11 world, there was a pre- and a post-Columbus world. Even though there were terrorist events before 2001, and even though Europeans had visited North America before 1492, the bombing and the landing changed everything. And so does this book.

We’ve long presumed that Chris C found a sparsely-inhabited continent of stone-age tribes who lived in communion with unspoiled nature. Even existence of the Incan, Aztec, Toltec, and Mayan empires further south did little to dispel the idea that technologically and intellectually superior Europeans made relatively short work of defeating unsophisticated enemies that just weren’t up to the task of combating armor and horses and firearms. And of course, there were those diseases.

Some recent works—Notably Jared Diamond’s Guns, Germs, and Steel—have done much to contradict this idea, but a host of myths about the provenance of America’s original humans has remained as long as history has been written about them. Now, some veils are being lifted, and Mann has taken it upon himself to summarize the anthropological and archeological discoveries of the last decade or two. The whole controversy is embryonic; much remains to be discussed and discovered. However, it’s my first clue that the argument was going on at all. I’m to be excused, I think, since it’s only in the last 15 years or so that some of these theories have gained even limited credence, and I don’t my ear to the archeological ground. But fas

It’s a transforming story.

First of all, the timing. Best guesses have been that humans have been on the two American continents for 10,000 years or so, and that the native peoples began building credible civilizations relatively recently—last couple of thousand years at best. It now appears that there were significant cities in the Americas contemporary with the great societies of western civ’s “origins”—Ur, Babylon, Sumer. Whoops.

Next, agriculture. Supposition is that what Columbus found were hunter-gatherers engaged in some sketchy crop cultivation. Suppose instead that those folks were master manipulators of their environments. That through fire and tools, they brought buffalo east where they could be easily harvested, made forests into parklike environs which could be easily navigated and hunted, cleared land where plants could grow, amended the soil,  applied fertilizer for abundance. What happens to the conventional wisdom then?

Well, it looks like all of the above probably happened to one degree or another in various locations.

Next, the numbers. What if the Americas were as densely populated with Indians as Europe was with Caucasians and other races? Whoops again.

There is not a hundred per cent agreement or clear evidence for all of these theories. However, the evidence is clear enough to call nearly every theory about the migration of peoples into the Americans and most theories about what they did when they got here. Mann such does a fantastic job of outlining the arguments and their supporting evidence that it’s clear, whatever the eventual conclusions, our whole idea of who we are and where we came from and when is about to undergo a seismic shift.