Throughout their entire history, the sedentary civilizations of China and Europe had to deal with nomads and "barbarians." This unique volume explores their drastically different responses: China "chose" containment while Europe "chose" expansion. Migration played a crucial role in this interaction. Issuing from two population centers, the sedentary one in the West and the nomadic one in the East, two powerful population streams confronted each other in the Eurasian Steppe. This confrontation was a crucial factor in determining patterns of Eurasian history--it destroyed existing states, created new ones, and drastically changed the balance of power. Even today, while Russian populations in Asia contract, the population pressures in China and Central Asia continue to build and are likely to spill over across the border. This book shows how we are witnessing the beginning of a new cycle of the age-old contest.