Probably upwards of half of County Durham's population died in 1349. Upsetting the ratio of land to labour in an area where serfdom was tottering on the edge of irrelevancy might have opened the door to greater individualism and entrepreneurial activity. Using tithe receipts, Ben Dodds has shown there was a ‘rapid recovery in aggregate output’ in the aftermath of the Black Death that fits A. R. Bridbury's ‘Indian Summer’, and rather than ‘retreating into subsistence production, peasants adopted new techniques and expanded output to meet the demands of the market’. Subsequently, aggregate production relative to pre-plague levels tailed off and there were a number of crises (in the 1390s, 1430s and 1490s); as A. J. Pollard has pointed out, ‘The fifteenth century after 1440 was a bleak era’ for the region, and the period preceding it was not strong either. Nevertheless, producers — including peasants — were able to respond to the market. Opportunities existed for peasants to take a chance to increase their fortunes. By 1500, there were individuals with sufficient resources to lease large parcels of land and even partial or whole vills. One such was John Hall, the son of William Hall, who took up lands in both Bishop Middleham and Sedgefield in 1500; his father had leased the demesne of Bishop Middleham and various parcels, with works, in 1485. In turn, John passed these holdings to his son, another William, in 1537.