Our species, Homo sapiens, emerged in Africa hundreds of thousands of years ago. From there modern humans followed in the steps of other kinds of humans—Homo erectus, Neandertals, Denisovans, and others—as they slowly spread across the planet. But the first H. sapiens who entered the Americas went somewhere no member of the human family had ever gone before. The process by which people explored, populated and adapted to the many different environments found across these continents was a momentous undertaking, one which began the rich and complex histories of thousands of different nations and communities.