Attention paid to Boko Haram, the terrorist insurgency in the Lake Chad Basin responsible for the deaths of tens of thousands of people and the displacement of millions more, often overreaches, veering into the sensationalist or speculative. Particularly since the organization pledged bayat (allegiance) to the Islamic State in 2015, certain circles in the media, policy bureaucracies and the academy have been quick to attribute shifts in the organization's tactics and developments in the region more generally to the ‘internationalization’ of the conflict. Alexander Thurston's Boko Haram: the history of an African jihadist movement is a delightfully grounded account of the group's rise that emphasizes the local dynamics that gave rise to the group and that continue to shape its activities.

The book helpfully divides Boko Haram's history into five phases: a phase of ‘open preaching’ between 2001 and 2009, a ‘decisive turn to violence’ in 2009, the group's turn to terrorist tactics between 2010 and 2013, its territorialization in 2013–15, and the internationalization and internal fragmentation that has characterized the organization from 2015 to the present (p. 2). In each chapter of the book, Thurston provides a meticulous account of the religious and political debates, as well as the intra-elite dynamics, that characterized the period, and describes the conditions that lead to the shift to the next phase.

Throughout the book, Thurston deftly integrates primary material from the group (including recorded sermons, written theological interpretations, correspondence between Boko Haram and other jihadist groups and within the group, and propaganda videos) with journalistic accounts, social scientific writing on the group and local history. He powerfully argues that Boko Haram has both theological and insurgent predecessors in the region, while paying due attention to the group's theological and tactical innovations. He asserts that ‘Yusuf invoked a set of interrelated doctrines as the religious basis for his political stances’ and describes how al-wala’ wa-l-bara’ (described as ‘exclusive loyalty … to those they consider true Muslims, and complete disavowal … of all others), al-hukm bi-ma anzala Allah (or a belief that ‘the true Muslim had to choose between God's laws and those of man’) and izhar al-din (operationalized to mean that ‘personal piety alone was insufficient: Muslims needed to confront the fallen society surrounding them’) shaped the organization's tactics and development (pp. 109–10). Thurston provides a description of the sect that unpacks what it means to be a Salafi organization, what it means to advocate for jihad, the space between the two distinct concepts, and the significance of Boko Haram's merging of them.

Thurston's description of the theological debates of the time is nuanced without being unapproachable and is entirely engrossing. The description of Yusuf's radicalization, a process described by Thurston as being facilitated by a combination of ‘hardliners’ within his own organization, frustration with the local political order and increasingly acrimonious confrontations with mainstream Salafis, is the most holistic treatment I have seen to date. The book takes religion seriously without engaging in sensationalist accounts, ‘othering’ adherents or securitizing Islam; it is a model of how to engage with ideologies and religion in conflict-affected settings to be emulated in a variety of fields. The intensity and characteristics of aspects of Boko Haram's violence have prompted some to describe the group as nihilistic; Thurston, however, engages with and contextualizes the theological positions of Boko Haram's leaderships that underpin the adoption of some of these tactics.

Boko Haram must also be commended for the unprecedented level of detail paid to local politics. Thurston details how seemingly unrelated and underexplored facets of the Nigerian political sphere affected the group's development. For instance, Thurston describes how urban sprawl in Maiduguri, the capital of Borno State, where Boko Haram's founder, Mohammed Yusuf, first established his own mosque and religious community in the 1970s, resulted in ‘a host of associated health and development programs, but also a breakdown in hereditary religious authorities’ mechanisms of surveillance and control’, further catalysing competitions over influence and legitimacy (p. 46). These details and discussions give the book heft and texture without making it clunky.

One of the few criticisms that can be levelled against Thurston's book is its focus on intra-elite dynamics. While there may be nuanced theological debates at the elite level, raids on Boko Haram camps frequently describe finding charms and amulets among the belongings of the foot soldiers that would be considered un-Islamic bid'aa (innovation) and condemned. The gap between the organization's theological policies and day-to-day practices is not addressed in the text. Having acknowledged this shortcoming, it is undeniable that Boko Haram is one of the best existing accounts of the rise and characteristics of the movement. Thurston's nuanced study of the local political dynamics that accompanied the founding and evolution of Boko Haram is simply unparalleled.