The introduction considers the problems with definitions of "viking", settling for "the years between 750 and 1050 regardless of any unifying principle or theme". There are chapters on individuals (gender, servitude, poets, "beserkers", effeminacy, outlaws, suicide), families (birth control, names, feuds, land, military households, dynasties), communities and associations (settlements and their role in defence and economic cooperation, lords and big men), districts and territories (which were not just waiting to "fulfill their destiny" through incorporation into states), and peoples (debates over nations and ethnicity).
"Different ecologies fixed territorial groupings for peoples living between the North Sea and the spinal mountains of the Scandinavian peninsula: deep fjords, steep slopes, diminished arable, shorter growing seasons and heavier snows sharpened competition between the farmers who had already settled the Norwegian coast as far north as the Lofoten islands in Roman times and earlier. Here, territories began as a long string of chiefdoms known collectively as Nor-vegr, the North Route, and therefore studied as the kingdom of Norway in embryo."
Then come chapters on politics (the many kinds of kingship that have been proposed, chiefs, freeholders and assemblies), war (where ships, horses, and spades were key), work (focusing on agriculture and the different kinds of farming regimes), and emigration (with colonization taking a variety of forms in different locations and political circumstances).
"Military dominance was impossible to sustain in the face of the well-organized manpower at the disposal of Wessex kings and some Irish rulers and Continental magnates; negotiation, alliance and conversion to christianity were attractive alternatives, and frequently offered. Guthrum got more by surrendering to king Alfred in 878 than by occupying his kingdom earlier in the year: great presents, recognition as a king and the peaceful occupation of wherever he wanted to settle outside Wessex."
And there are chapters on the past (sagas and verse, myths, lineages, and genealogies), the present (ethics, law, cults and gods, imitations and communications), and the future (hopes, fears, death, and notions of an afterlife).
"The origin-myths of tribes and peoples form a special category to our way of thinking, a bridge from myth towards, if not into history, but that is not how they seem in oral cultures which do not separate things in this way. ... Even the wonderful Gotland genesis in Guta saga, which incorporates all an ethnologist or social anthropologists could want of archaic thought, is couched in the language of the thirteenth - fourteenth century, and will hardly do as a relic of the viking-age. The dominance of myth in ideas about the past among the Norse must be taken on credit, as a strong probability, rather than the richly-documented field of research which is sometimes the meat of well-attended conferences."
A postscript surveys modern research into the Vikings: the "old schools" of archaeology, anthropology, philology (including runology, skaldic studies, and toponymics), and folklore; "new methods" such as palaeoclimatology, palaeobiology, and genetics; and "new philosophies" such as processualism, post-processualism, the archaeology of gender, and postmodernism.
Christiansen himself draws on these, and on psychology, anthropology, political theory, and a range of other disciplines, but he is critical, often acerbically so, of the wilder theorising. Of claims for the existence of "secret warrior societies", "blood-brotherhood", and suchlike: "These fantasies have sucked blood from anthropology and still walk upright, independent of evidence". Or, of sacred kingship theories: "there is no evidence whatever that any king was ever sacrificed either among or by the Nordic peoples".
There is no shortage of books on the Vikings, but the popular ones are often of a romanticising bent and the scholarly ones narrow in focus. The Norsemen in the Viking Age is fully referenced and Christiansen displays a magisterial command of both sources and secondary literature, but he never gets bogged down. Scholars and lay readers alike should read him for a lively, broad-ranging, and solidly grounded survey of the Viking Age.