Humanity has long drawn on the past to make sense of, and negotiate, a challenging present. In our increasingly connected digital world it stands to reason that there might be parallels and congruities in how the ancient past is mobilised for contemporary political legitimation in multiple national and international contexts. Bonacchi's approach draws on big data to examine how aspects of the past may appear in populist and nationalist discourse on social media. This is the first “systematic analysis of the international currency of the repertoire of objects, places, people and practices within populist nationalist speech that relate to the Iron Age, Roman and post-Roman heritage of contemporary Europe” (p. 170). Bonacchi's work, in fact, spreads beyond Europe (where the focus is on Italy and the UK) to the United States, considering the leveraging of the same Roman past in debates about immigration during the Trump presidency. This monograph is the latest output of the AHRC-funded Ancient Identities in Modern Britain project, based between Durham University, UCL and the University of Stirling from 2016 to 2019. As with the project's earlier outputs (e.g. Hingley et al. 2018), it affirms the importance of critical understandings of the past, while highlighting the ongoing challenges of communicating these to the public. Although the communication gap between archaeologists and heritage professionals and the public is well-known, what is less apparent is how to bridge that gap. Bonacchi's monograph provides what could be one key plank: a vision for public archaeology and heritage based on “social heritage” or “studies that aim specifically to understand the processes and results of people's use of the past to interpret the reality in which they live” (p. 8); in the following eight chapters she demonstrates the value in this approach.

The first three chapters (Part 1) are theoretical—considering the value of big data for heritage research—and methodological, presenting the key datasets and data-collection methods used for the analysis in Part 2. Bonacchi effectively highlights the value of using “found data” (data that are “organic and generated in real time”, p. 15), which have the potential to reveal what is usually internalised—how individuals draw on the past to make sense of contemporary problems. Chapter 3 discusses debates about nationalism and its relationship to identities and attitudes towards borders and immigration, emphasising how, within this, dualities are driving narratives of heroism and imperialism. Binaries such as ‘civilisation versus barbarism’ are frequently embedded within myth-making, supporting or arguing against nationalist ideologies; Bonacchi provides an important reminder that they are “often deployed in apparently incoherent or even in contradictory ways” (p. 47).

These dualities and their contradictions are evident in Chapters 4–6, which present the three main case studies: Euroscepticism and nationalism expressed on the Facebook pages of populist political parties leading up to the Italian General Election in March 2018; uses of the ancient past (Iron Age, Roman, early medieval) in discussions about Brexit on social media; and pro- and anti-populist nationalist discourse surrounding the US/Mexico border and immigration debates during the US presidential election in November 2016. The scope of data analysed in these chapters runs to the millions of tweets, posts, comments and replies on Twitter and Facebook. There are some clear and well-articulated themes running throughout these chapters. One example is how the myth of the decline and fall of the Roman Empire is frequently leveraged to support localism and the exclusion of people who supposedly ‘do not belong’. Ranging from “multiculturalism is a sign of decline” (in Italy, p. 68), to how the British National Party (BNP) claimed that “hordes of immigrations from Africa and the Middle East” would be to blame for “the greatest civilization ever created [the West] … suffer[ing] the same fate as the Roman Empire” (BNP, p. 88), or for strong border walls (à la Hadrian's Wall) in the US to prevent such a fate. It is unsurprising that the theme of (Western) identity obliteration is often levied, linked as it frequently is to racist ideologies. While there are too many similarly valuable points embedded in these chapters to feature them all here, one final point that deserves mention is how, in the discussion of links made in the press between Trump's wall on the US/Mexico border and Hadrian's Wall, Bonacchi takes care to underline the problem of how archaeologists have frequently normalised the existence of walls (p. 122). When such a practice is seen as ‘natural’, it becomes increasingly difficult to critique or mobilise against.

The final two chapters act as an extended conclusion, examining the role of expert authority in discussions of the ancient past in contemporary political dialogue. Bonacchi questions how historiographical debates about the ‘end’ of the Roman Empire are reflected in the historical consciousness evident on social media, and, importantly, considers the extent to which it is possible for experts to communicate ‘accurately’ in a highly manipulated media context. Recently, there has been much discussion about archaeologists as political actors and this chapter (7) is a worthy addition to the ongoing dialogue.

Perhaps one of the most surprising results of the monograph is the very limited number of mentions that are made in reference to antiquity; for example, of the over 12 million tweets comprising the collection on the US Immigration and Travel Ban, only three referred to Hadrian's Wall. The statistical significance varies per dataset, yet the reader is struck by the overwhelming sense that the ancient past may be appearing in political discourse less frequently than assumed. Regardless, Bonacchi is able to draw out a significant amount of interpretation based on the instances when there are references made to the ancient past. Although the author discusses the small numbers involved, this comes rather late in the narrative; earlier discussion would have helped to situate the reader. It is clear that while quantitative research may be driving forward the digital humanities and heritage work similarly oriented around big data, qualitative methods will always be vital, particularly in cases such as these. Social media will probably remain a crucial area for research on the uses of the past for political discourses in the present, and the work presented in this monograph will provide a strong foundation for future research focusing on social heritage.