This study is concerned with the cultural and economic role of long-distance trade in an age when the technological breakthrough of the late eighteenth century had not as yet fundamentally changed the structure of Asian and European societies and state-systems. The period of history covered is long by any standard other than those of astronomers, geologists, historians of climate, and archaeologists. From the rise of Islam in the mid-seventh century to the beginning of European imperialism in the 1750s eleven centuries are spanned, a period during which the world saw the completion of an entire lifecycle for civilisation in general. In ecological terms alone, the old balance between human society and its environment was about to be replaced by a new order. The effects of the changes involved still continue to haunt us today, and there is no sign as yet of a possible equilibrium. For the period under study, the main historical movements stand out in bold relief. The diffusion of Islam as a religion and a way of life, if it marked the final break between the classical age and the new forces of expansion in much of the Mediterranean and the Near East, also created distinct zones of political tensions which ultimately checked its growth and destroyed the earlier sense of Arab intellectual triumph. The process of Christian reconquista in the Iberian peninsula was a forerunner in its chronological context of the great oceanic discoveries which the Spanish and Portuguese explorers were to initiate in the fifteenth century.