In 723 the Anglo-Saxon missionary Boniface, according to his first hagiographer Willibald, kick-started the conversion of the Hessians by chopping down their sacred oak at Geismar and building an oratory from the wood which he dedicated to St Peter. One could not ask for a better microcosm (from the paper of John Henry Clay) of the issues considered in the essays in this stimulating book for the period when Christianity had to fit itself into sacred landscapes that were already occupied and make them its own. The book has its origins in the interdisciplinary project ‘Making Christian Landscapes’ based at University College Cork and funded by the Irish Heritage Council. Roughly a third of the papers derives from the project and draw on its study areas. The rest of the volume originates, for the most part, from an excellent conference held at Cork in 2012, and demonstrates the potential of comparative studies for generating new ideas and a better understanding of the process of conversion in different areas of Atlantic Europe. Included are papers, of varying depth and length, on Wales (2), Scotland (1), northern England (3), western France (3), Galicia (1), Hessia (1), the Netherlands (1), Norway (1) and Iceland (1).

The regional summaries are a very valuable resource in themselves, particularly for areas such as Galicia (José Carlos Sánchez Pardo) or Drenthe (Netherlands) (Jan Kolen) on which there is little available in English. But it is the parallels and contrasts between the regions which makes the book as a whole so absorbing. The editors draw attention to some of the topics of interest in their introduction, but anyone reading is likely to be struck by possible links that had not occurred to them before. Does, for instance, the religious protective function argued for churches on the borders of some of the Irish kingdoms also hold good for the nunnery of Whitby in north Yorkshire (discussed by Tom Pickles) founded not just on the coast, but, like some of its dependencies, in a former Roman signal station? Of course, before such parallels can be drawn one must be sure that like is compared to like. The regional studies bring out how variable the surviving sources of evidence can be, and how that, as well as different traditions of study, can appear to give a particular slant to the evidence. How far later sources can be projected accurately back into the conversion period is also an issue. Anne Connon (Irish Munster) and Anne Lunven (eastern Brittany) both make cogent cases for dedications to native saints that are mostly first recorded in later centuries as being likely to belong to a relatively early period of church consolidation before 800. But such continuity needs to be demonstrated rather than assumed. Elisabeth Rio-Zadora argues that it has been too readily believed (she suggests particularly by English historical geographers) that parish boundaries fossilised much more ancient divisions in the landscape; rather, boundaries were subject to repeated manipulation and adaption to changing circumstances.

One of the greatest differences between chapters concerns the speed at which it is believed that the Church imposed its own ideologies on the landscape and became a medium for change. Sam Turner and Chris Fowler make the case for the conversion in Northumbria bringing in new technologies that led to social change, but Rhiannon Comeau finds little sign of this in her carefully nuanced study of areas of western Wales where the Church was adapted to fit into distinctive local patterns of agriculture and landscape use. Also up for debate, as with Boniface's actions in Hessia, is how far early Christian sites were set up in active opposition to a pagan landscape, or whether there was a greater need to fit in and adapt to existing patterns of religious presence.

One thing that is particularly striking from the studies is how scarce churches were in the first centuries after conversion. Adrián Maldonaldo demonstrates how even sites with an early monastic history in Scotland are marked by a first stage of cemeteries and domestic and craftwork-activity before the foundation of a church. It is evident from several regions that the Christian experience for many congregations did not involve initially much in the way of worship within a church, and that a variety of loca sancta in the landscape (including cemeteries) are likely to have been more significant. Jan Kolen (Drenthe) and Elisabeth Zadora-Rio (Touraine) both argue that what are often thought of as the essential components of the medieval parish did not come together until a relatively late point in the tenth and eleventh centuries. There is a challenge here for understanding the ordinary early medieval person's experience of the introduction of Christianity which has scarcely begun to be met. Of course, there are regional differences in chronology. Norway and Iceland did not have any church organisation before the eleventh century, but Sæbjørg Walaker Nordeide and Steinunn Kristjánsdóttir carefully marshal the evidence for individuals and groups who might have considered themselves Christian before that date and for a gradual Christianisation of the landscape. When church organisation was introduced into Iceland there was a rapid proliferation of timber churches at the most important farms. This would seem to be an indication of the very different expectations for church provision by the eleventh century from that in the earlier periods when Christianity was first adopted in other parts of Atlantic Europe. Altogether this is a most stimulating volume, and Cork University Press is to be congratulated for their high standards of production at a very reasonable price.