The obstacles to documenting the intellectual progression of senior members of one of modern history's most secretive regimes are not small. Yet Matthew Galway's new work, exploring how and why Communist Party of Kampuchea figures Hou Youn, Hu Nim and Pol Pot absorbed and adapted Maoism to their own economic, political and social context, overcomes some of those challenges to shed new empirical and theoretical light on how revolutionary thought “travelled.”

Establishing simple historical facts – names, dates, places – about Cambodian and Chinese domestic and international politics and revolutions over the half-century sweep of the book is no mean feat. The purges of intellectuals and archival materials in both countries makes this kind of survey difficult, and the temporal framework of the book helps reveal where new, or newly unearthed, sources fill in gaps in hard-won knowledge. Galway draws on materials found in the Shanghai Library, the Shanghai Municipal Archives, and Xiamen University's Center for Southeast Asian Studies, among others. His location and analysis of information from Sino-Khmer Daily, published by the Battambang Overseas Chinese Party Organization beginning in 1956, could alone make for an intriguing journal article.

Galway focuses his efforts specifically on these three members of the Paris-educated leadership of the Communist Party of Kampuchea. But in order to contextualize their thinking, he first profiles how Mao himself became the “gold standard of an ideal revolutionary and theoretical architect” (p. 36), to make the case for a contrast between “bureaucratic” and “faith” Maoism (pp. 63–65). In assessing the Chinese Communist Party's efforts between 1965 and 1975, Galway documents ideas that led to disastrous domestic policy outcomes, but also an increasing effort to globally promote Maoism as critical to challenging imperialism. His discussion of Pol Pot's 1965–1966 visit to Beijing makes a compelling case as to why Pol Pot returned to Cambodia with a particular perception of Maoism – one distinct from Hu Nim's and Hou Youn's.

They were, Galway writes, the “theoretical architects of a Maoist vision that became DK” (p. 109). Exploring the progression of their interpretations via their dissertations, Galway identifies parallels between Hou Youn's and Mao's investigative-analytical approaches (p. 128). Hu Nim, by contrast, understood the need for radical transformation at all levels of Cambodian society, from elites to peasants (p. 136). But as the two were driven from Phnom Penh by head of state Norodom Sihanouk in 1967, they and DK allies entered a new phase of recruiting support for their movement. Galway argues that the two “had tremendous acumen when it came to peasant grievances because they had lived that life before” (p. 158), but ultimately it was Pol Pot's “faith Maoism” that dominated the movement as the DK eventually won the civil war and took power.

Drawing on speeches and other surviving documents, Galway notes that between 1975 and 1979, Pol Pot's beliefs and practices followed thought processes similar to Mao's, noting that “Pol Pot's rejection of Maoism in developing Polpotism [was], in fact, very Maoist” (p. 199). He concludes by arguing that these Cambodian Communists drew on their own experiences and contemporary realities to adapt Maoism to their circumstances and their political needs.

Some may argue that a theoretical approach is less robust if specific individuals’ lived experience is to be considered a key explanatory variable. In other words, did the ideas “travel” less well to other senior DK members who studied in Paris, and, if so, how and why? Nevertheless, it is hard to suggest that particular experiences and interpretations of cultural, economic, and social realities did not influence how Pol Pot, Hou Youn, and Hu Nim chose to interpret political ideologies.

One potentially compelling – if chilling – strategy for testing the relative strength of the “travel” theory would be a careful weighing of Galway's approach relative to the powerfully repressive dynamics of the DK. Did Hu Nim and Hou Youn truly believe in these evolving ideas, or did they espouse them in order to maintain power in the movement and avoid falling afoul of it? That both were executed by the DK suggests that that experience should also be considered. To be clear, both could be true, and it would be telling to understand whether – as was also the case with Maoism – ideas about class, power and struggle were deeply twisted for personal gain. Galway certainly acknowledges the grim outcomes in both countries; it would be excellent to also read his deep historical research on this puzzle.