ABSTRACT
This introduction presents an overview of key concepts discussed in the subsequent chapters of this book. With the emergence of the Christian Roman Empire in the fourth and the Islamic Caliphate in the seventh century, it might seem for a while that empire was the adequate form of political organization for a universal religion. Therefore, ethnicity hardly ever occurs in its pure form; it has to attach itself to other, more tangible forms of community a homeland, state, army or religion. It is interesting to compare the complex tension between universal religion and universal empire in Christian and Islamic empires with an example from the Buddhist world. In, Guntram Hazod argues that the development of a Tibetan empire in the seventh century CE was due to the common interest of clan groups in establishing control over the Silk Road, whereas the adoption of Buddhism, a religion not yet shared by all, caused its decline.
