The United States is a nation of common people from marginal environments. In spite of contemporary America’s preoccupation with coats of arms, few of our ancestors were the children of privilege. Nor did they come from lush plains or fecund valleys. More often it was the mountains and hill country they left behind, where stony soils, forests, or harsh weather made farming difficult and made them willing to tear themselves away and take their chances in far-off America. They were Irish from Kerry and Donegal, Italians from Sicily and Abruzzo, Romanians from the mountains of Transylvania and Swedes from the forests of Smaland and Dalarna.