From antiquity onwards, north-western Europe was divided into two large bodies, both from an economic and social point of view. The first was constituted, to the south of the Rhine, by the former provinces of the Empire conquered by the Romans at the end of the first century BC and in the first century AD. In the third century Barbarian tribes on the borders of the Roman Empire (the limes) exerted growing pressure on this territory which was expressed in various forms: military raids, then systematic occupation of the territories after the withdrawal of Roman troops (Great Britain, Toxandria), or accommodation, by the infiltration of families or the settling of groups sanctioned by treaties between the Germanic tribes and Romans. Ancient Gaul was totally occupied from the sixth century on by the Franks, who progressively dominated the whole of the Great Northern European plain, towards the east as far as Saxony and to the north as far as the border of Denmark. The second body had as its single common point the fact of never having been conquered by the Romans and consisted of Germanic, Scandinavian and Celtic populations (Wickham, 2010). Within these two zones, peasant families were faced with very different agricultural systems and landownership structures before the Germanic conquest. In Great Britain, the withdrawal of Roman troops was followed in a few decades by the abandoning of earlier forms of ownership and settlement systems. On the continent, the processes were more complex in the sense that the changes which affected the settlement of the countryside could stretch over several centuries and that the new forms of ownership and land occupation resulting from these changes were spread by conquest, from the seventh century, from Frankish Gaul towards the north and the east (Frisia, Saxony), and to the west (the Anglo-Saxon kingdoms) by the influence exerted by Carolingian ideological models (Wickham, 2009). In this chapter, we examine three regions during the early middle ages: 1) north-western Europe under Frankish hegemony (northern France, Belgium, the Netherlands, and north-west Germany), 2) England, and 3) Scandinavia. These lands were in constant contact through ideological and religious influences, mainly from the Frankish regions, migration, trade flows and wars. The place occupied by the family unit in rural production at the beginning of the period studied is still poorly understood today in terms of the whole of the regions of northern Europe. The study of family morphology and the structures of rural production show that the narrow family group, composed of a couple and their children, became the principal unit of production, reproduction and organisation in the rural society of the West. It took on its fundamental features during the early middle ages at the moment when conjugality became the ideological model spread by Christianity and 1 Our thanks to Chris Wickham and Alexis Wilkin who reads the first drafts.