God's War: A New History of the Crusades

In central areas of this Afro-Eurasian region, those of Christian and Muslim observance and rule, the religious and political structures rested on settled agrarian economies and populations. Byzantium and the Islamic states shared a flourishing commercial system that supported gold currencies and towns, while in Christian western Europe, by 1000 urbanization – or, in the perspective of the Roman empire, reurbanization – had only recently begun to accelerate along the major trade routes north of the Alps: the North Sea and north-west Mediterranean coasts, the Rhine, Rhône, Seine, Loire, Thames. In Italy towns and cities had survived more robustly since the collapse of the late Roman economy and civilization, even if on a far smaller scale than further east. The economic imbalance was reflected in the size of cities in the eleventh century. In the eastern Mediterranean, the great metropolis cities boasted populations of hundreds of thousands – Baghdad perhaps half a million; Old Cairo slightly less; Constantinople perhaps 600,000 at most. In Muslim Spain, 100,000 people may have lived in Cordoba, although some estimates make it much more. By contrast, the largest western Christian cities – Rome, Venice, Florence, Milan, Cologne – hovered around 30–40,000. Paris and London in 1100, sustained by a largely rural hinterland, probably counted about 20,000 each, the equivalent of rather third-rate cities in the Near East or less. Elsewhere in northern Europe, cities were even smaller, while some important towns could muster only a very few thousand inhabitants. One of the striking features of the following two centuries lay in the massive growth in western urban populations, but even by 1300 cities such as Paris, pushing towards 100,000, still barely competed with the great entrepôts of the eastern Mediterranean.

Even with heightened economic and commercial activity in western Europe, the imbalance of trade remained evident, the west having to rely on an often limited silver coinage as the wealth flowed eastward and southward, gold, much of it from west Africa, never reaching or staying in large enough quantities to sustain currencies beyond the Pyrenees, Alps or Danube. International trade revolved around luxury items, notably spices and finished textiles such as silk from the east and slaves, fur, timber and some metals from the west and north. Local exchange, primarily of foodstuffs but also certain basic living materials, such as wool and woollen cloth, provided the main engine of regional commerce in the rural economies. The mosaic of local economies varied widely across the region: cereals, wheat in the more southerly areas, rye and oats further north; wine in the south, beer in the north; sugar cane in Syria; olives around the Mediterranean; fishing everywhere along the enormously long shores of Afro-Eurasia. The growth of towns in Europe between the Alps and the Atlantic indicated an acceleration in such commercialization, a process that acted as a liberating dimension for large sections of the peasant communities who were mainly tied to the land by law, hierarchy, custom, coercion and economic necessity. In market places, transactions may have been taxed and regulated but they tended to operate outside bonds of tenure. Slavery, once ubiquitous in Roman and post-Roman Afro-Eurasia, persisted in the Arab world, but was gradually dying out in Christian lands, whether through moral distaste driven by the church or economic prudence.