In Europe, the cross went north and east as the centuries unrolled: from the Dingle Peninsula to Estonia, and from the Alps to Lapland, ranging in time from Roman Britain and Gaul in the third and fourth centuries to the conversion of peoples in the Baltic area a thousand years later. These episodes of conversion form the basic narrative here. History encourages the belief that the adoption of Christianity was somehow irresistible, but specialists show the underside of the process by turning the spotlight from the missionaries, who recorded their triumphs, to the converted, exploring their local situations and motives. What were the reactions of the northern peoples to the Christian message? Why would they wish to adopt it for the sake of its alliances? In what way did they adapt the Christian ethos and infrastructure to suit their own community? How did conversion affect the status of farmers, of smiths, of princes and of women? Was society wholly changed, or only in marginal matters of devotion and superstition? These are the issues discussed here by thirty-eight experts from across northern Europe; some answers come from astute re-readings of the texts alone, but most are owed to a combination of history, art history and archaeology working together. Martin Carver is Professor of Archaeology, University of York.