One problem with scholarly research into land reclamation has been the tendency to concentrate on two questions – how and why did it happen – leading to an over-emphasis on technological innovation and demographic and commercial pressures. This has obscured far more fascinating and significant questions – what were the social consequences of pre-industrial land reclamation? What kinds of societies emerged as a result of land reclamation? These questions are addressed through a comparative historical analysis of two cases of land reclamation in the medieval period: the peat lands of Holland (the Netherlands) and the Po Valley plains (Northern Italy). In the paper it is shown that medieval land reclamation led to the emergence of two very divergent societies, characterised by a number of different configurations in; (a) power and property structure, (b) modes of exploitation, (c) economic portfolios, and (d) commodity markets. In the final section, a further question is considered. To what extent were either of these societies inherently better configured to negate the potentially disastrous effects of land reclamation on the natural environment? In the conclusion it is argued that more ‘equitable’ and ‘freer’ pre-industrial societies were better placed to deal with the consequences of environmental degradation than those marked by polarisation and repression – even when those polarised societies made recourse to capital investment in technology.