Both Indie and China are densely-populated state with sophisticated culture and ancient origin. Both countries are ethnically and religiously diversified. Despite its resemblances, histories of two states were quite different. China during most of its history has one unified centralized empire, meanwhile India was mix of many kingdoms, constantly fighting about hegemony. Indeed, some Indian rulers (Mauryan, Gupts, Mughals) succeeded to united greater part of Indian peninsula under his scepter, however all of these empires were ephemeral and quickly broke up into number of smaller warring states. Why?