Nationalism in an Overheating World: An Introduction to Thomas Hylland Eriksen's Life and Works

Boldly rooted in inventive, brilliant sociocultural anthropology and deeply committed to cross-cultural comparisons, Thomas Hylland Eriksen (1962–2024) was a true polymath, whose academic itinerary is greater than many of us could imagine from our own fields of study. Nationalism scholars know him mostly for his work on nationalism and ethnicity (Eriksen 1993a) or internet radicalisation (Eriksen 2001, 2007). This symposium explores other aspects of Thomas' unique trajectory, while connecting it with his distinctive understanding of nationalism. Weaving together insights from various disciplinary areas into a bold synthesis, Thomas had a rare ability to see connections where others saw divisions—part of one great, unfolding conversation about the predicament of the contemporary world. Thomas' work became familiar to me when I was a PhD student at the London School of Economics (LSE) in the early 1990s. Indeed, our first international articles both appeared in the same issue of Ethnic and Racial Studies: he analysed the issue of language diversity in Mauritius (Eriksen 1990) from a perspective that seemed to be complementary to mine, on Catalonia (Conversi 1990), and this immediately caught my attention. Thomas' article was later extended into a comparison between two island communities, Mauritius and Trinidad and Tobago (Eriksen 1993b). It was these travels and human encounters that gave him an earlier insight and an advanced awareness of the slowly irradiating patterns of global homogenisation associated with environmental destruction and manifested, according to each case, as overtourism, overexploitation, overconsumption, overpopulation, amplifying neocolonial oppression (Eriksen 2022b). Yet, it was only many decades later that we had our first substantial intellectual encounter, rich in exchanges, shared concerns, synergic perspectives and skilful observations. It was on the occasion of a conference organised by the Czech anthropologist Petr Skalník in Prague and Paris (Skalník 2022; Skalník et al. 2023), to commemorate the 25th anniversary of Ernest Gellner's death (postponed by a year due to the Covid pandemic and then held online). Having written extensively on the expanding polycrises of the Anthropocene (Eriksen 2016), Thomas was chosen to comment on my essay connecting Anthropocene thinking with Ernest Gellner's theory of nationalism. He responded with acute observations and genuine enthusiasm: It was like two kindred souls finally discovering each other's theoretical compass and epistemological world vision (Eriksen 2022a). Having graduated (laurea) in anthropology myself, I saw that we shared a common way of exploring human beings's relationships with their environment and culture, besides a joint understanding of the current state of the world. Our collaboration culminated in several initiatives, chiefly the 2023 workshop on the Future of Diversity mentioned here in both Hessen's and Posocco's contributions. Thomas' search for truth (and awareness of its consequences) was profound, and he communicated it with a strong warmth, capable of conveying affability, kindliness, compassion and moral strength, even in times of great turmoil. Thomas knew that in his lifetime, unfortunately shorter than all of us would have hoped, he would not have seen the consequences of the destruction carried out by a minority of his contemporaries. Economic growth calculations can easily show that a world with finite resources can only be exploited at the expense of those who will succeed us (Murphy et al. 2021). Thomas' generation was not supposed to pay for the expected extent of damage and universal suffering it had laid down for the future, and for which nobody is prepared (Goussebaïle 2025; Hessen 2024). As more and more people continue to buy cars, fly and semiunconsciously introduce plastic into the bodies of their children (Ragusa et al. 2021), the damage is passed on to the shoulders of the coming generations—beginning with our very own offspring (Goussebaïle 2025)—with drastic consequences. Thomas' last writings were therefore indirectly dedicated to addressing the problems faced by today's youth—those who will inherit not just our national heritage, which may well be spent by the time they grow up, but also our actions, inactions, attitudes, habits, including the damage against everything and everyone living both in our proximity as well as in faraway lands. As most of his friends and colleagues knew, Thomas had been seriously ill for many years. In a memorable TED talk about his watershed Overheating project and book, he appeared to be more physically challenged and emaciated than many of us had remembered him; yet he was in full spirits, intellectually sparkling, releasing vitality from every pore, trenchant and uncompromising in the strength of his message—to launch his cry of alarm for the fate of the world.1 All who knew him were deeply touched by his resilience, as he always bounced back after highly debilitating sessions of intensive therapy. Every time he recovered, rebounded and rallied, it looked like a miracle. Thomas knew, then, the value of time as passing quickly, dissolving like sand between our fingers (as it became for him, and is indeed the case for everybody), and how to spend the final years of his life fully and meaningfully: by approaching new areas of knowledge, exploring, making interconnections and writing about them. In his personal life, Thomas did not simply live for himself; he existed in symbiosis with the social and environmental context in which he worked and travelled. He always maintained a youthful, lively curiosity and a spirit of enquiry. This led him to explore novel interconnections and interlinkages across the disciplinary spectrum of human and natural sciences, by venturing beyond disciplinary boundaries into new fields such as biology, as Dag Hessen's contribution here clearly shows (Hessen 2024). Among Thomas Hylland Eriksen's last pioneering efforts was a courageous attempt to explore the deeply running interconnections between cultural and biological diversity, particularly the combined loss of both, which presaged the beginning of an era of deeper devastation, the Anthropocene (Conversi 2025). As a geological epoch, the Anthropocene is most often identified with the onset of industrialisation, the very same time frame that Ernest Gellner understood as giving birth to nationalism (Gellner 2006). This is no mere coincidence: Both industrialisation and nationalism were deeply intermingled, and both were interrelated with the steamrolling force of capitalism and its destructively homogenising impact (Conversi 2022). Thomas agreed: ‘the Anthropocene began, at first tentatively and embryonically, as part of the same general historical process that produced nationalism’ (Eriksen 2022a: 176). In one of his last lectures, Thomas confirmed that ‘historically, there is an almost exact fit between the era of nationalism and the era of fossil fuels beginning of in the late 18th/early19th century’.2 The Anthropocene is a geological epoch in which nationalism still thrives with its highly mimetic capacity and chameleonic adaptability, just as nations risk becoming human fossils. The Swedish political and environmental scientist Andreas Malm cogently noted that the Anthropocene, however misplaced or oblivious to class and capital the concept may be, is also the era of fossil fuel extraction, processing, combustion, consumption and conversion to petrochemical products, well condensed in the notion of ‘fossil capitalism’ (Malm 2014). Capitalism's dependence on fossil fuels broadly overlapped with the industrialisation process that brought a set of other dramatic consequences, which we are only now beginning to grasp as deeply interrelated—nationalism, genocide, cultural homogenisation and climate change—as Thomas understood well (Eriksen 2021). But industrialisation would not have created such a set of problems if it had remained confined within the United Kingdom or northern Europe. The shift amplified when industrial consumption spiralled out of control, leading to mass consumption and, hence, overconsumption—to what Thomas described as global ‘overheating’ (Eriksen 2016). What this means is that whenever we hear in the news that this is the hottest day on record, it may also turn out to be the coldest day in the foreseeable future. Such is the self-inflicted wound and destructive trend initiated around the 1960s and greatly accelerated after the Cold War—as Thomas clearly describes. Inevitably, this will involve billions of people moving across boundaries and trying to reach those regions and states where they hope to survive (Sæten 2025). Yet, these very countries are beginning to erect barriers and boundaries to halt the foreseeable influx. Of course, nothing similar has happened before in human history, and nobody seems thus to be prepared for the event. The root cause identified by Thomas, in syntony with current science, is overconsumption leading to ‘overheating’ (Eriksen 2016). Many things are uncertain in the near future, but few things can be more certain than the impact of climate change. In a short note, Thomas wrote: ‘Eventually, states may collapse owing to civilizational breakdown, but in all likelihood humans will survive, although perhaps in very diminished numbers and with much reduced social complexity’ (Eriksen 2022a: 176). How much suffering this would imply for humans and other animals, as well as the devastation of plant life, nobody is prepared to say yet. Most scientists, particularly Earth Scientists, identify the production patterns established across the West since the late 1950s or early 1960s (depending on latitude) as the beginning of a well identifiable geological era based on rapidly co-occurring events and parallel itineraries of ‘extraordinary human consumption’ (Syvitski et al. 2020). To various degrees, historians increasingly share this chronological outline, first foreshadowed by John McNeill (McNeill 2001), and more famously reconceptualised by McNeill himself in his watershed history of ‘The Great Acceleration’ (McNeill and Engelke 2016)—passing through Dipesh Chakrabarty's grappling with the tension between the vastness of geological time and the more immediate timescales of human history (Chakrabarty 2009, 2018) and Prasenjit Duara's reckoning with nationalism in a finite world (Duara 2021, 2025). These new layers of rapid stratigraphic change manifest themselves in worryingly new ways: Nuclear physicists trace the shift back to the spread of radioactive isotopes since Hiroshima and Nagasaki and, more markedly, following the thermonuclear weapons (H-bomb) test explosions of the 1960s (Waters et al. 2015). But most scientists, including chemists and health scholars, emphasize the rise in CO2 emissions since the 1960s (earlier in the United States) and, later on, the global diffusion of microplastics and nanoplastics from the most hidden recesses of the oceans to the highest peaks in the Himalayas (Napper et al. 2020). Recently, these have also been found in disturbing quantities in most human tissues (Carrington 2020; Landrigan et al. 2025). This was, in fact, part of the ‘overheating’ planetary trend that Thomas saw approaching. His book Overheating was not about nationalism and did not explore nationalism's relationship with climate change, but it contained a global and all-encompassing vision of the world that is now fast coming upon us with astonishing speed and which he redefined as ‘acceleration of the acceleration’—following in the footsteps of McNeill's The Great Acceleration (McNeill and Engelke 2016). Thomas skilfully combined Gellner's vision of nationalism as ethnic and cultural homogenisation with his latest observations of a planet under siege and ravaged by human carelessness as the approaching storm rapidly unfolds (Hallam 2019; Malm 2018; Malm and Carton 2024). Of course, as an anthropologist he resisted the notion that this shift was being manufactured by generic and generalised human beings (Conversi 2025). Indeed, only a tiny minority of billionaires, politicians and military cadres (although certainly not all of them) can ultimately be held accountable for the likely trail of interconnected catastrophes and possible tipping points (Maitland et al. 2022). The five contributions included in this symposium in honour of Thomas Hylland Eriksen proceed from various disciplines, adopt different viewpoints and approach his legacy from both nationalism studies and a shared concern about ongoing global change. Chris Hann situates Thomas' critique of sovereignty within a longer lineage, contrasting it with Gellner's statist emphasis and Malinowski's federalist vision (Gellner 1987). By historicising these theories, Hann shows how sovereignty has shifted from a safeguard to a rhetorical device in the era of globalisation, while urging anthropologists to engage with both supranational institutions and grassroots alternatives. In doing so, he reaffirms anthropology's responsibility to confront the crises of state power, cultural diversity and ecological survival. Siniša Malešević links Eriksen's work on time to nationalism (Eriksen 2001), showing how digital technologies have fragmented linear time yet enabled 24/7 grassroots nationalism. Far from eroding nationalism, the digital age amplifies it through decentralised, algorithm-driven participation, making citizens' key agents in spreading and policing nationalist content. Dag O. Hessen's piece highlights Eriksen's exploration of biocultural homogenisation, connecting biodiversity loss with cultural erosion and the legacy of homogenising nationalism. He stresses Eriksen's legacy of advocating long-term thinking, empathy and cooperation in a world fractured by nationalist competition and conflict. In this context, consumerism and short-termism, the latter also typical of far-right nationalism, remain two important drivers of both climate and biodiversity crises. Lorenzo Posocco recalls Eriksen's powerful critiques of nationalism as a driver of the ‘Homogenocene’ (Conversi and Posocco 2024). Sceptical of politics as a resource to address the climate crisis, Eriksen looked to grassroots and indigenous resistance to preserve diversity. Posocco highlights that Eriksen's final years were among his most prolific, combining ecological urgency with a humanistic commitment to resilience and semiotic freedom. He concludes this article by remembering Eriksen's openness and support for younger scholars. Gabriella Elgenius highlights Eriksen's concept of the ‘grammar of inclusion and exclusion’, first presented in a 2014 ASEN lecture at LSE. This framework refers to the linguistic, symbolic and institutional mechanisms through which societies define belonging, often reinforcing hierarchies via language, dress and religion. Eriksen's metaphor of the ‘inverted refrigerator’ vividly illustrates how groups overcommunicate their differences—coldly to outsiders but warmly within—revealing paradoxes in identity and boundary-making. Elgenius shows how he extended this analysis to globalisation and climate change, where exclusionary practices intensify, as seen in the Brexit ‘left behind’ narratives that racialise inequalities and scapegoat migrants. Eriksen further linked these dynamics to ecological issues, arguing that cultural and species erasure in the Anthropocene represents a ‘parallel othering’ of nature and culture, driven by a controlling, uniformity-seeking ideology. In summary, Thomas Hylland Eriksen was a unique and influential figure in the fields of social anthropology, biology, history, philosophy, literature and other fields. His book Overheating, in particular, as well as many other publications and activities, reflects his insights into natural science. Together, these testimonies bear witness to Eriksen's rich legacy and capacity to open up new perspectives across disciplines. This should never be far from nationalism studies scholars and their endeavour to investigate beyond appearances. The data that support the findings of this study are available from the corresponding author upon reasonable request.