Aggersborg is the largest of five tenth-century circular fortresses from Denmark, known as the Trelleborg-type fortresses after the location of the first of these to be archaeologically investigated in the 1930s. They were built under King Harald Bluetooth as an expression of political power, Aggersborg probably representing the first in the sequence and constructed c. AD 970–75. They served a practical purpose: their relatively even distribution across Denmark suggests control of the landscape and important communication routes. At the same time, the building of fortifications was also a symbolic act, signalling Harald as the equal of near-contemporary European rulers such as the West Saxon King Alfred and his successors, responsible for the construction of the West Saxon and Mercian burhs, or the Emperor Otto II, who also engaged in fortification building on a significant scale. Occupation of the Trelleborg fortresses was, however, short-lived. According to the authors of this volume, this was because the taxes and manpower required “could only be maintained in times of trouble” (p. 15). Their abandonment—after only a few years—is linked to the death of Otto II (and his succession by a young child) in 983 and the subsequent end to the aggressive stance of the German Empire.

This excellent publication details the results of investigations that started more than three-quarters of a century ago, and represents a slightly condensed version of a report published in Danish, also in 2014, by the same authors. The book is subdivided into eight chapters with accompanying appendices. Chapter 1 briefly sets the scene, emphasising the significance of the fortress in the tenth-century political landscape. Chapter 2 (‘Aggersborg's location and history’) places the fortress within its landscape setting, drawing attention to its location on the Limfjord, an important thoroughfare between the North and Baltic Seas during the Viking Age, and discusses other archaeological discoveries from the region. The history of the fortress after its abandonment is also discussed. Interestingly, it seems that the fortified area was never reoccupied after its short lifespan, although various settlements sprang up nearby. Written evidence further reveals that from the eleventh century a royal manor existed in the vicinity, while an isolated church with an associated cemetery was constructed on the hill slope overlooking the fortress. At some point during its subsequent history, the area of the fortress was used for agricultural purposes, the ramparts gradually eroded by ploughing. The treatment of the obsolete earthwork is thus not dissimilar to that of the fortress of Oost-Souburg in the province of Zeeland in the Netherlands, one of around five ringforts of probably later ninth-century construction in this area, which are generally regarded as prototypes for the Danish forts. It is possible that the avoidance of the enclosed area had symbolic reasons—a deliberate disassociation with the values associated with the fortress—although the authors prefer a more practical explanation for the discontinuation of settlement in this area, namely its location near a boundary of the royal manor. Chapter 2 also provides a brief history of the Aggersborg project. Chapter 3 presents an in-depth discussion of the investigation methodology and terminology. Chapter 4 (‘The Viking Age settlement’) discusses the settlement that immediately preceded the construction of the fortress, representing the first Viking Age rural settlement in Denmark to be excavated on a significant scale. As preservation was exceptionally good, this site is key to a better understanding of Viking Age architecture in Denmark, comprising both large post-built and sunken-featured buildings, many of which seem to be associated with textile production, in particular loom weights. This evidence, together with the possible interpretation of the fill of one sunken-featured building as a ritual deposit, is strongly reminiscent of Helena Hamerow's (Reference Hamerow2006) work on ‘special’ deposits in Anglo-Saxon settlement contexts, although this is not explored in depth.

Chapter 5 (‘The fortress’) describes the results pertaining to the fortress itself. The earthworks, internal layout and structures are described in detail, followed by a summary of finds associated with the occupation of the fortress, including non-local pottery and evidence for specialised crafts. This includes textile working (spinning), generally seen as a woman's craft and therefore deemed unusual in a military context, but occurring more frequently in the Trelleborg-type fortresses and, indeed, other near-contemporary ringforts, such as the Dutch examples mentioned previously. These finds suggest that the population of the fortress was not exclusively military in character, but the authors do not expand on this. Chapter 5 finishes with a discussion of the fortresses in their wider context, starting with a discussion of the other Trelleborg-type forts and related sites in Scandinavia, before moving on to relevant fortresses situated elsewhere in Europe, including the aforementioned English burhs and the Dutch ring fortresses, as well as the German Großburgen and contemporary Slav fortifications. A section on dating completes this chapter.

The final chapter comprises a detailed catalogue of the finds from Aggersborg, most of which relate to the settlement underlying the fortress. The main categories are building materials, pottery, stone artefacts, domestic and personal equipment, metal dress-accessories, beads and other objects made of amber and glass, coins, weapons, evidence for horse riding, skating, agriculture, fishing, textile working and other crafts, painting a vivid picture of the wide-ranging contacts and the everyday activities of the settlement's inhabitants. Objects of earlier (prehistoric) and later (medieval and post-medieval) date are discussed separately. The chapter concludes with an overall summary of the character of the settlement and its cultural connections.

Overall, this report is a detailed and well-presented summary of the results of the investigations of this internationally important site. The volume is lavishly illustrated throughout, with many beautiful colour photographs and large maps. If—as indicated in a few instances above—the discussions tend towards the descriptive rather than the speculative, the volume remains a wonderful starting point for more interpretative work, and belongs on every Viking archaeologist's bookshelf.