Sir Michael Postan's view of the demographic history of the English countryside before the Black Death, expounded in M. M. Postan (ed.), Cambridge Economic History of Europe, i: The Agrarian Life of the Middle Ages (2nd edn, 1966), M. M. Postan, The Medieval Economy and Society: An Economic History of Britain in the Middle Ages (1972), and other works, was enormously influential, but from the late 1980s onwards has been increasingly challenged. See, for instance, Bruce M. S. Campbell (ed.), Before the Black Death: Studies in the ‘Crisis’ of the Early Fourteenth Century (1991), which reject Postan's Malthusianism. The ‘Postan thesis’ was that the growing population in the 13th and 14th centuries was faced with land hunger, that smallholdings predominated, that land reclaimed from the edges of the fens, moors, woods, and marshes was of poor quality, that the fertility of soils declined, and that the average expectation of life declined during the century after 1250. The series of crop and livestock disasters between 1315 and 1322 was seen as a Malthusian crisis. The enormous pressure of the population on the inadequate resources led to a declining standard of living until the pressure was dramatically eased with the Black Death. The thesis has been modified by demographic historians, who have argued that the 1315–22 crisis was ‘more than a mere fluctuation, but less than a turning point’, and by agrarian historians, who have argued that an adequate living could be earned even on the so‐called margins. See Mark Bailey, A Marginal Economy? East Anglian Breckland in the Later Middle Ages (1989), and Christopher Dyer, Making a Living in the Middle Ages (2002).