The wake of the UN Climate Change Conference (COP) 2021 in Glasgow and the by now familiar despair from environmentalists and scientists over perceived inaction in the face of knowledge, is a good moment to explore the history of how knowledge about our environmental crisis has been produced, and to consider how knowledge moves from the margins of public consciousness to the mainstream. This is, broadly speaking, the subject of David Larsson Heidenblad’s book Den gröna vändningen (“The Green Turn: A New Knowledge History on the Breakthrough of Environmental Questions in the Postwar Period”), which centres on the case study of Sweden in the second half of the twentieth century.
David Larsson Heidenblad lays out his case for the history of knowledge (kunskapshistoria) in the introduction to the book, arguing convincingly for the importance of what he terms “samhällelig cirkulation av kunskap” – the social circulation of knowledge (p. 22). It is this movement, by which knowledge comes from scattered and marginal voices to take up a place in the social mainstream, that he is interested in teasing out in his study. Larsson Heidenblad differentiates the history of knowledge from the history of science, cultural history, and the history of ideas (idéhistoria) through precisely this focus on the process of knowledge circulation and the interplay between individual actors, networks, and audiences.
His introduction, entitled “The Green Turn”, explains the structure and reasoning behind the book. Starting from what he considers the “breakthrough” year of 1967, the author follows individual threads radiating outwards and exposing a range of different perspectives. A key feature of this approach is his focus on three individual “knowledge actors”, whose lives and actions made a distinct contribution to the development of the Swedish debate. Hans Palmstierna, Barbo Soller and Birgitta Odén – scientist, journalist, and historian, respectively – are all important players in the story of Sweden’s environmental knowledge. Moreover, they each illustrate different channels and degrees of direct and indirect influence by which knowledge is communicated and takes hold.
In his second chapter (and first substantive chapter of his case study), “The Breakthrough of the Environmental Question in Sweden, Autumn 1967”, Larsson Heidenblad makes the case for the significance of the publication and reception of Palmstierna’s book Plundring, svält, förgiftning (“Plundering, Famine, Poisoning”), putting it into context alongside other publications of the period, including Rachel Carson’s Silent Spring. The chapter explores the role of Palmstierna in the breakthrough of environmental questions and in galvanizing a range of environmentally concerned knowledge actors. Larsson Heidenblad follows this up with a third chapter that doubles back to the immediate postwar period in Sweden in order to analyse the knowledge landscape that Palmstierna’s book emerged into, covering the period from 1948 to 1967 and looking at dominant discourses, such as the threat of nuclear war and overpopulation.
The fourth chapter takes up the stories of the other two knowledge actors Larsson Heidenblad focuses on, the journalist Barbro Soller and the historian Birgitta Odén, exploring their personal trajectories as professional women and environmental pioneers from 1964 to 1969. Barbro Soller, who Larsson Heidenblad describes as “en unik kunskapsaktör” (a unique knowledge actor, p. 91) is an important figure in her amplification of environmental knowledge in the public sphere, as well as in her own reporting. Birgitta Odén is a different kind of knowledge actor, engaged outside the public eye in trying to develop the field of environmental history in Sweden, an endeavour that was not crowned with immediate success but that nonetheless had an impact on Sweden’s intellectual landscape. Larsson Heidenblad shows how these women’s networks and spheres of influence resulted in different kinds of knowledge circulation.
Chapter Five returns to the breakthrough unleashed in autumn 1967 and its exploration of the mobilization of the public in engaging with environmental concerns, looking in detail at the immediate responses in the twelve months following the publication of Palmstierna’s book. Chapter Six once again pans out to take a longer view, investigating the rise of modern environmental movements from 1959 to 1972 as the context for the outcomes of the 1967 “breakthrough.” The final substantive chapter Seven is titled “Conflicts and Media Storms, 1971–72” and analyses in depth the controversies surrounding Palmstierna in particular and the politicisation of environmental questions.
The concluding chapter, “A New History of Knowledge”, starts by detailing an exchange of letters in 1971 between Hans Palmstierna and a schoolboy, Mats Lidström, seeing in it an illustration of knowledge produced not just by scientists, politicians, journalists and activists, but also in the mind of an eleven-year-old child (p. 194). Through the social circulation of knowledge explored in the previous chapters, Larsson Heidenblad argues, there has been “ett samhälleligt kunskapsgenombrott,” a social knowledge breakthrough (p. 194). This is his argument for taking 1967 as the moment of the “green turn,” and in a wider sense his argument for the lens of the history of knowledge, with its emphasis on the circulation of knowledge at different levels from the societal to the individual.
David Larsson Heidenblad will be known to many on Twitter for his blog A Year of Academic Writing, which has also been published in book form. It is reassuring as well as pleasing to note that Den gröna vändningen is indeed extremely competently written. As well as having a clear and approachable prose, Larsson Heidenblad makes judicious use of signposting, both in the body of the text and in the many subtitles that assist the reader in navigating the book. The lively illustrations by Ragni Svensson deserve special mention; it is unusual to have creative illustrations in an academic book, and they showcase the book’s potential appeal beyond an academic audience – something that Larsson Heidenblad explicitly mentions as his intention in the introduction (pp. 18–19). The book’s potential audience will be greatly swelled with the recent publication of a version of the book in English, translated by Arabella Childs and available open access from Manchester University Press. Overall, this book presents a polished and muscular argument for the history of knowledge, and is a thoughtful examination of how awareness of environmental issues was formed and shaped in post-war Sweden, with implications for how we think about environmental knowledge today.
 Hans Palmstierna, Plundring, svält, förgiftning, Stockholm 1967.
 Rachel Carson, Silent Spring, Boston, MA 1962.
 Both the blog and the book have been published in Swedish as well as English. In Swedish: David Larsson Heidenblad, Ett år av akademiskt skrivande, URL: <https://davidlarssonheidenblad.blogspot.com/> (07.12.2021); Ibid., Ett år av akademiskt skrivande: Erfarenheter och arbetstekniker för unga forskare, Lund 2020. In English: David Larsson Heidenblad, A Year of Academic Writing, URL: <https://ayearofacademicwriting.blogspot.com/> (07.12.2021); Ibid., A Year of Academic Writing: Experiences and Methods for Early Career Researchers Lund 2021.
 David Larsson Heidenblad, The Environmental Turn in Postwar Sweden: A New History of Knowledge, Manchester 2021.