In 1491 Mann explored the newest findings about what the Americas were actually like before the "Old World" set foot on it (as opposed to the dated perceptions that we can't seem to easily shake loose). Now Mann explores how the world reacted, and was affected, by this meeting.

I can't even begin to summarize what information is covered here, but here is a list of things that are discussed: potatoes, tomatoes, tobacco, sugar, rubber, gum, rum, Madeira, mosquitoes, malaria, yellow fever, smallpox, silver, guano, Africans, Indians, the Chinese, Spaniards, Basque miners, slavery, pirates, and a lot more. We may know a little about each of these subjects but here their connections are explained and, even better, the consequences and results of those connections are fully explored.

To say this is exceptionally interesting would be an understatement. A lot of the information presented here is new to me, or at least new in the sense that what I learned as separate histories is shown here to have connections that were never explicitly pointed out (and I never would have guessed at). (Case in point, everyone is taught that the Spanish mined South America for its silver, but who ever pointed out that half of that silver ended up in China? And the reasons why it ended up there? And the impact it had there? Etc.) The author does reference this book, but I'm pretty sure he expands on the original idea rather than simply rehashing it(and if I ever read that book, I'll insert an update about that here).

I consider this a far more historically dense book than 1491 since the cultural and biological exchanges between the Old and New Worlds, as can be guessed, was (and continues to be) very complicated. This is just as much a worthy sequel to 1491 as 1491 is a worthy 'prequel' to this book.