In this engaging new study of revolution, Silvana Toska sets out to answer a series of questions that have puzzled scholars of revolution for decades. When and why do revolts spread? What determines when they will spread? Why do only some succeed? Importantly, Toska asks a further question, which the author claims (and I agree) has yet to be properly scrutinized: why is the spread of revolution confined to world “regions” during major waves of revolutionary upheaval?

To answer these questions, the author turns to emotions—specifically, anger and hope. Or, in Toska’s own words, to the “emotional mobilization” of shared anger and hope and a dynamic wherein “individual emotions can turn into group emotions” (p. 6).

The book offers a theoretical synthesis built on top of prominent insights from psychology, contentious politics, and civil–military relations. “Emotions,” writes Toska, “are ontologically prior to and drive cognitive mechanisms” (p. 20). In certain circumstances, or conducive opportunity structures, revolutionary protest is able to spread. That spread is based on “emotional arousal [that] is limited to individuals who share a common identity.” The way in which the military then reads this situation and responds is a function of, in part, their leadership structure and ties with the incumbent regime, but also the emotions mobilized by revolutionary crowds.

To support her argument, Toska compiles an original dataset of all “rebel movements” between 1945 and 2013. Toska’s argument relies as much on the successful revolution as it does on the failed one, thus she includes both in her dataset. It is worth examining how this dataset might compare to those collected by Mark Beissinger. Toska then enriches these data with a newly coded variable on “identity proximity” in order to test whether revolutions mainly spread to regions with a shared identity, be it ethnic, linguistic, religious, and territorial.

This is, in all, an impressive data collection effort. But one is left wondering how sure can we be that revolution does not just spread to regions that have both a common identity and common structural problems. I was struck by how well one of her activist interviewees managed to strike at the core problem here: “We are the same people,” this interviewee said, “suffering under different but equally bad regimes” (p. 27). So why does revolution spread among these people—because they are the “same people” or because they are “suffering under different but equally bad regimes”? Is this about how we identify with the mobilization of others or is it about the structural conditions we commonly suffer? To answer this question in a multivariate setup, confidence in the operationalized variables is essential. While Toska convincingly advances a new measure of “identity proximity,” we are not closer to understanding the role of emotion. The author addresses this by suggesting that protest size can be viewed as one proxy for emotional mobilization. But the size of protest encodes multiple other explanatory variables––the likelihood of repression perhaps chief among them. A similar problem besets the measurement of opportunity structures (by which Toska mainly means the presence of mobilizing structures), which is measured with Polity II score and degree of prior mobilization. While the first is a distant proxy, the second is endogenous and circular. Hence, it is difficult to be confident of the lessons we should derive from the various multivariate setups tested.

In subsequent chapters, Toska principally relies upon interviews conducted with numerous revolutionary activists across multiple countries in the Middle East and North Africa (MENA). The interview data Toska has laboriously collected is an equally impressive data source. The author also uses Iran as an astute reference point when interviewing MENA revolutionaries. She shows that, while the 2009 protests in Iran did not inspire an obvious emotional reaction in the recollection of her interviewees, it did so for the Tunisia and Egypt protests. The focus, additionally, on awareness of autonomous organizations rather than active membership in them is an especially observant corrective to previous attempts at measuring the effect of such organizations through surveys. I would have liked a deeper investigation of this crucial point. Instead, Toska moves on to a discussion of the military and how they read crowds, which I felt ultimately distracted from the genuinely new arguments about the perceptions of revolutionary crowds.

The final chapters are dedicated to case studies from Egypt, Tunisia, Syria, and Saudi Arabia. Here, Toska is piecing together the building blocks of her argument and does a good job to relate why emotions should be considered seriously. Yet the reader is distracted by discussions of why theories of scholars such as Timur Kuran fail to apply in the case of Egypt. These are, in this reviewer’s opinion, unnecessary and unhelpful to the argument.

In all, this is an important addition to the literature on revolutions. The book is at its strongest when scrutinizing the taken-for-granted, namely, how revolution is circumscribed to world “regions.” Here, the book offers genuinely new lessons for the study of contentious politics by advancing a measure of “identity proximity” and examining how and why this precedes the emotional arousal necessary for the spread of revolutionary protest. As for emotions more generally, future work will need new modes of gauging this nebulous construct: tools that contribute to a more rounded theoretical understanding of the apparent causal primacy of emotions in explaining revolutionary upheaval. That said, the book is both a valuable contribution to existing scholarship on protest in the MENA region as well as the place of emotions in the study of this convulsive and visceral phenomenon called revolution.