Late Roman decadence and plundering Vandals: these are the clichés about the so-called Migration Period. But how did a new cultural unity called Europe emerge in the first millennium from the highly developed Roman South and the barbaric North? Around the birth of Christ, Europe was divided into the advanced South of Mediterranean cultures and the underdeveloped North of Germanic and Slavic tribal cultures. These cultures knew neither writing nor stone settlement construction, a standing army, or a monetary economy, let alone cities with fire departments and waste collection. How could the onslaught of the barbarians deliver the death blow to the Roman Empire? Peter Heather reexamines this age-old question in light of insights into ethnogenesis and modern migration research. From the Hunnic invasions to the Vikings, he explores the dynamics of European migration movements.