I realize that we are often wary of making these kinds of broad generalizations about different cultural groups—and with good reason. This is the form that racial and ethnic stereotypes take. We want to believe that we are not prisoners of our ethnic histories.

But the simple truth is that if you want to understand what happened in those small towns in Kentucky in the nineteenth century, you have to go back into the past—and not just one or two generations. You have to go back two or three or four hundred years, to a country on the other side of the ocean, and look closely at what exactly the people in a very specific geographic area of that country did for a living. The "culture of honor" hypothesis says that it matters where you're from, not just in terms of where you grew up or where your parents grew up, but in terms of where your great-grandparents and great-great-grandparents grew up and even where your great-great-great-grandparents grew up. That is a strange and powerful fact. It's just the beginning, though, because upon closer examination, cultural legacies turn out to be even stranger and more powerful than that.