Past & Present 190 (2006) 35-81
Over the past two decades there has been an impressive escalation in the literature surrounding the marked economic and commercial growth that characterized the two centuries or so before the advent of the Black Death. This period of growth occurred on a virtually global scale, in that, at the very least, it involved a great swathe of interconnected trading networks stretching from China to the British Isles. For Europe this has been described in a number of important publications, such that 'commercialization' is now widely accepted as a valid characterization of the growth of the economy during the twelfth and thirteenth centuries. As John Hatcher and Mark Bailey have pointed out recently, however, commercial models for the Middle Ages suffer from a certain theoretical immaturity:
This article aims to address the critique of Hatcher and Bailey by providing a more logical formulation for medieval commercialization, particularly through a tighter elaboration of the mechanisms by which society and commercial opportunity interacted to produce population change. We are restricting our analysis here to England — a country for which an unrivalled wealth of documentary materials for issues relating to the medieval economy has survived — during the two centuries leading up to the arrival of the plague, but we recognize that much of what we are saying has application for other periods, as discussed in the conclusion, and undoubtedly for many other parts of Europe, if not elsewhere, during pre-industrial times. Put baldly, our argument is that there was a powerful conjunction between entrepreneurial activity and population growth, and that the former tended to lead the latter. Also central to our argument is the belief that the current scholarly emphasis on the real wages of individuals has given an unduly negative view of how this economic growth affected society at large, and that total yearly family income is probably a much better, and certainly more optimistic, indicator of medieval society's well-being.
One of the problems of setting 'commercialization' in a suitable theoretical framework is that it is such a diffuse, all-embracing concept that it is difficult to grasp intellectually, and certainly in its relationship to population growth. All considerations of commercialization must start with classical writers such as Adam Smith, David Ricardo and Thomas Malthus, but, even here, the internal logic that underlies commercialization is not inherently obvious. Part of the problem perhaps lies in the insufficient distinction between those exogenous forces that impinge upon commercialization — either positively or negatively — and those endogenous elements central to the process of commercialization itself. Here we label these forces as 'externals' and 'internals'. 'Externals' are those mostly unplanned happenings that encourage or forestall economic activity. They include war, disease, weather, sudden discovery or depletion of precious metals (particularly when such precious metals are drawn from sources outside the state or country), and injudicious state intrusion, especially in such things as excessive taxation or purveyance (that is, the expropriation of food and other supplies for various royal purposes, especially for the king's armies in times of war). All these, by and large, are imposed upon the process of economic development, and particularly entrepreneurship, rather than being internal to it. Indeed, in the medieval context, it is often held possible to describe the fortunes of the economy solely in terms of these externals, as historians with a monetarist bent have sometimes sought to do. Thus the period of growth from, say, the late twelfth century to the beginning of the fourteenth might be explained in terms of relative peace, a relatively disease-free environment, better weather conditions and the discovery of new sources of silver; while the downturn over the fourteenth and fifteenth centuries might be explained...