This thesis investigates the influence of socio-economic conditions on crop cultivation and consumption practices in Britain during the Roman, Saxon, and Medieval periods. The archaeobotanical remains of staple field crops (cereals, pulses, and flax) are used as evidence for the decision-making of farmers and the consumers of their produce. The introduction, expansion, contraction, and discontinuation of crops consumed and under cultivation are considered against the backdrop of their environmental and political context, in order to identify the impacts of changing economic and social structures on agricultural practice and staple crop consumption. During the Romano-British period, changes in farming strategies were primarily aimed at increasing total cereal output, rather than meeting specific consumer preferences. Distinctive patterns of crop consumption were found at consumer sites (such as military sites, London and other large towns) that reflect the prioritisation of pragmatic concerns with the logistics and cost of food provisioning over Romanised ideals of cuisine. Decision-making in the Saxon period was, in contrast, demand-led. Each new introduction represented an improvement on spelt when utilised for a specific purpose. Instead of two general purpose crops (spelt and barley), the Saxon and Medieval crop spectrum comprised the "best" bread-making grain (free-threshing wheat), the most nutritious animal feed supplement (oat), the longest and strongest straw for construction and craft-working (rye), and the preferred brewing grain (barley). The demands of farmers, rather than urban consumers, were the catalysts for innovation, although the new introductions were subsequently adopted as cash crops as opportunities for market sale increased. The dietary variety seen in late Saxon and High Medieval towns is less an expression of consumer choice, and more a reflection of the stratification of wealth within these communities as a greater variety of culturally inferior foodstuffs was consumed by poorer households.