A common problem regarding some regional archaeological questions is that they quite often lack a broader perspective. If we add to this a very limited empirical foundation, we have the appropriate conditions for an endless debate, with no expectations of any substantial advance. This is, more or less, the point raised by Carlos Fabião (Reference Fabião2002: 189) on the central subject of the work reviewed here: the tower structures linked to the early Roman presence in the southwest of the Iberian Peninsula.

From the 1960s onwards, these enigmatic constructions have been the subject of research from multiple angles: from written sources to the analysis of building techniques, excavation, and field survey. Nevertheless, this development has been very variable geographically, leaving great gaps in our knowledge. With this book, Joey Williams provides an up-to-date overview of one of the areas in which this phenomenon acquired greater relevance: the Portuguese region of Alentejo. Above all, it is a fresh approach that looks with new eyes at an old problem.

The work represents a synthesis of the fieldwork carried out by the author between 2010 and 2013 in close cooperation with local archaeologists, especially with Rui Mataloto. Their joint excavation of the fortim (‘small fort’) of Caladinho, in the municipality of Redondo, becomes the setting for the interpretative proposal that these sites represented points of Roman territorial control in the early stages of the formation of the Province of Lusitania. As outlined in Chapter 1, the central thesis defended by Williams in this book is that these settlements became the scene of an encounter in which the main actors were not strictly military units but, more probably, civilian colonists and local populations. On the one hand, they had to give a response to the conditions of insecurity and conflict during this moment of transition; on the other hand, they were active agents in the establishment of a new social and political order. This is a duality that is very hard to clarify, since it lies at the very core of the ‘Romanization’ concept (Woolf, Reference Woolf2014). With a critical perspective on the events-based discourse stemming from written sources, Williams calls our attention to individual and collective decision-making processes, with a special consideration of the role of indigenous populations facing the Roman intervention. Despite the absence of a particularly detailed theoretical approach, the repeated references throughout the book to the concepts of negotiation and entanglement make clear that the fundamental prism through which these issues are addressed falls within the theoretical spectrum of agency (Dobres & Robb, Reference Dobres and Robb2000; Stockhammer, Reference Stockhammer2012).

Beyond these broader questions, Chapter 2 offers a basic spatial and temporal background to the study area. After a brief geographical description, the author provides an overview of the main historical facts related to the Roman conquest of the Iberian southwest. This chapter also offers a state-of-the art overview of the archaeology of the Alentejo region. Williams presents a tight synthesis of the main archaeological sites of the area from the Iron Age to Imperial times, with a critical discussion of arguments regarding chronology and cultural identity. Particularly interesting here is the discussion of how it might be possible to perceive the material traces of Roman military forces, a topic with a growing presence in the scientific debate (Sala & Moratalla, Reference Sala Sellés and Moratalla Jávega2014; Pera & Vidal, Reference Moret, Frederiksen, Müth, Schneider and Schnelle2016). To what extent these military contingents became embedded in the indigenous settlements or created their own infrastructures (castella, castra, praesidia,…) is still an open question that has strong implications for the understanding of this transition period. The case of Castelo da Lousa (pp. 42‒43) is probably a good example of this ambiguity between civilian, domestic italic architectonic formulae and the military appearance characteristic of towers.

In Chapter 3 we move from the regional environment of the Alentejo to the broad periphery of the Roman Empire, in search of textual or iconographic references of surveillance structures. This extensive section is justified only insofar as we assume (before any analysis of the evidence in the Alentejo is presented) that this is the right functional interpretation for the Portuguese sites. Perhaps it would have made more sense to include this chapter in the global analysis of landscapes of surveillance offered in Chapter 7. The cultural and chronological frameworks of these references are so heterogeneous that the purpose of their compilation in relation to the Alentejan case study becomes a bit unclear (see the work by Moret, Reference Moret1990 and Reference Moret, Frederiksen, Müth, Schneider and Schnelle2016, for a good example of the changing meaning of textual references to watchtowers and other kinds of isolated fortified structures). In short, towers and fortifications should be interpreted within their own archaeological contexts.

Returning to the Portuguese case, Chapter 4 presents the catalogue of sites on which Williams’ spatial analysis is based. Here the author draws mainly from descriptions and graphic material published by Mataloto (Reference Mataloto2002), as well as from the distinction established by this researcher between fortins and recintos torre (‘tower enclosures’). This terminological differentiation obliges Williams to stop at one of the problems complicating the discussion around this type of settlement: their denomination. A confusing variety of concepts has been deployed, not only in Portuguese, but also, in a very important way, in Spanish research on the subject. This has been very intense in the last twenty years, with many contributions encouraging the debate and clarifying many questions about the functionality and chronology of these buildings. Many of these works are included in the bibliography of The Archaeology of Roman Surveillance, but Williams' discussion in the book focuses almost exclusively on Portuguese research. Paradoxically, in this case the gaze from a distance cannot completely overcome the barrier of current political boundaries, which are alien to the original territorial unity of the Lusitanian province.

Chapter 5 is devoted to the results of the excavations conducted at the site of Caladinho. Williams doesn't hesitate to judge this settlement as an archetype of the small fortifications described in the catalogue. Even more, he considers it as a valid reference for the interpretation of other sites in neighboring areas, like the castella of the Lower Alentejo region. Undoubtedly, the most interesting aspect of this section is the attempt to define the identity of Caladinho's constructors and dwellers. This is obviously a crucial problem, and the effort to address it through a detailed study of the material record is as meritorious as necessary. Here, Williams addresses a profound issue: how can the gradual introduction of foreign products in indigenous contexts be interpreted? How can we assess the role played by these objects in an environment of interaction between different social formations and cultural groups? However, the scarce material evidence available leads (again) to an ambiguity without an easy solution. Are these foreign objects expressions of an aspiration to imitate the patterns of Roman lifestyle, or the direct expression of the desire to preserve elements of a foreign identity far away from home?

It is not clear then whether the occupants of the fortins were local communities with close ties to the outsiders, members of auxiliary forces, or a first generation of foreign settlers. Although most of the book does not make a categorical statement on the subject, the most plausible idea would be that they are indigenous ‘collaborationists’, who use local building techniques and dwelling habitus, but who imitate and use imported elements. This system of indirect control should offer interesting similarities with other landscapes of surveillance structured by the Romans, like the Egyptian network of isolated watchtowers around Mons Claudianus. I think this emphasis on the local civilian factor is an appropriate response to some excessively militarist interpretations of the material record of the Late Republican period in the Iberian Peninsula.

Up to this point in the book, it is assumed that the main function of the fortins is surveillance. But to what extent do the available data support this hypothesis? Chapter 6 presents a spatial analysis at a territorial scale in order to test this idea. This section focuses exclusively on visibility as a fundamental explanatory variable. Williams makes a proper contextualization of the role of these calculations in archaeology, adopting a critical stance regarding their use. Visibility analysis is understood as a means to observe the general behaviour of the sample of sites, rather than as a reconstruction of the actual visibility in one specific time and place. Discussion of the results provides a case-by-case assessment of the proportion of visible land around the sites and their connections with neighbouring settlements. It is assumed that these variables are indicative of the topographic prominence of these structures. The main conclusion is that the fortins were not randomly installed in the landscape. They didn't work as a maximized surveillance network (close to the model of the panopticon) but as a ‘patchwork’ structure focused on specific areas of interest. Although the author's viewshed analysis is careful and exhaustive, I believe that it could have been significantly improved with a statistical treatment of the data, or with other GIS calculations that allow the locational criteria of the sites to be characterized in more detail (see, for example, Fairén, Reference Fairén Jiménez2007; De Reu, et al., Reference De Reu, Bourgeois, De Smedt, Zwertvaegher, Antrop, Bats, De Maeyer, Finke, Van Meirvenne, Verniers and Cromb2011)

Finally, what lessons can we draw from the Alentejo case for the wider understanding of surveillance systems in the Roman world? This is the theme of Chapters 7 and 8. A series of territorial control models are presented, as well as their similarities and differences with the context analysed by Williams. This comprehensive and comparative approach is undoubtedly the most valuable aspect of the book. The author manages to go beyond the narrow regional debate, and this is certainly one of the challenges for the future study of this phenomenon. Williams’ determination to overcome a particularist vision is worthy and intelligent. His Archaeology of Roman Surveillance brings us closer to the study of the materiality of forms of power and control.

In conclusion, we can say that this is an estimable contribution, a book that introduces us to the complex reality of the scenarios of interaction between indigenous and colonial communities. It will certainly put in the spotlight a topic within the Roman archaeology of the ‘far west’ of Europe that until now was relatively unknown beyond the regional scientific literature.