In September 2001, when then President George W. Bush referred to the so-called "war on terrorism" as a "crusade," he was, consciously or otherwise, drawing upon perhaps the most widespread, if myopic, image in the West for describing Muslim-Christian relations. In the twenty years since Bush's unfortunate statement, there has been a dramatic increase in works, both popular (e.g., Carl Medearis's Muslims, Christians, and Jesus: Gaining Understanding and Building Relationships [Minneapolis, 2008]) and scholarly (e.g., Brill's monumental Brill's Christian-Muslim Relations: A Bibliographical History, https://brill.com/view/serial/HCMR1BP), devoted to the history of this crucially important, if often fraught, relationship. Michael Frassetto's book is a very readable and solid contribution to this growing literature.

Frassetto, who has explored medieval Muslim-Christian relations in several previous essays, begins by situating his study in relation to several notable scholarly landmarks in this field. Specifically, he refers to the important work of Norman Daniel, R. W. Southern, and, most recently, John Tolan. As Frassetto puts it, his book is not intended "to replace those earlier works, but instead to complement and supplement them by undertaking a new examination of the long and complex history of Muslim-Christian relations in the Middle Ages, and perhaps examining that relationship in new ways and addressing old questions from new perspectives" (xviii). As a complement and supplement to those earlier works, his book is largely successful. It is especially successful in highlighting how medieval Latin Christian identity and even doctrine were forged, to a significant extent, through interaction with Islam.

Like Southern and Tolan (but not Daniel), Frassetto arranges his study chronologically from the rise of Islam in the seventh century CE to the mendicant "missionaries" of the thirteenth century CE, culminating in Dante's Divina Commedia. Throughout, he emphasizes the impact of apocalypticism on Christian thinking about Islam and Muslims and the paradoxical nature of a relationship that could combine religious violence and hostility with significant cultural exchange.

As Frassetto's initial chapters indicate, both apocalypticism and paradox mark the early phase of Muslim-Christian relations. In their attempts to make sense of the rise and rapid expansion of Islam, early medieval Christians characteristically turned to the Bible, and most especially to apocalyptic biblical texts and to apocalyptic interpretations of other Scriptural passages. Here, like Tolan, Frassetto focuses on the importance of the Apocalypse of Pseudo-Methodius (ca. 692), "the most widely read early Christian text about Islam written in Syria" (34). Frassetto identifies various strategies (e.g. treating Islam as a Christian heresy) used by Christians to locate Islam in a framework that would render the new "sect's" successes intelligible (and thereby perhaps less threatening).

In chapter 3, entitled "Convivençia," Frassetto turns his attention to Christians and Muslim in early medieval Spain. In this chapter, he seeks to demonstrate how the period of so-called convivençia("co-existence") saw, in a paradigmatic way, both religious hostility (e.g., the Cordoban martyrs) and remarkable cultural vitality and exchange (e.g., the library at Cordoba). According to Frassetto, "the dichotomy that existed in Umayyad Spain between deep hatred and violent conflict on the one hand and a form of tolerance and peaceful coexistence on the other hand is representative of the relationship between Christians and Muslims throughout the Middle Ages" (91).

In chapter 4 the focus shifts from the Iberian peninsula to Charlemagne and Muslim-Christian relations in the Carolingian era. Here, Frassetto argues persuasively that under the Carolingians and beyond (eighth through tenth centuries CE), Christian rulers and ecclesiastics saw Muslims as potential political rivals or sometimes even as allies, but not as "some theological anti-Christian foe" (118). Given the welcome attention to Carolingian developments, one might expect some more explicit engagement with the "Pirenne Thesis"--especially in light of its "enduring attraction" (cf. Bonnie Effros, "The Enduring Attraction of the Pirenne Thesis," Speculum 92.1 [2017]: 184-208). However, Frassetto does not mention Pirenne by name, even while presenting, via Michael McCormick, a rather different view on the impact of the Islamic expansion (105-106).

A "turning point" comes with chapter 5 and the early eleventh century. Again inspired by apocalyptic notions now associated with the new millennium and despite (or perhaps because of) somewhat deeper familiarity or closer contact with the "Saracens," the Christian authors Frassetto surveys increasingly present a more hostile attitude toward Islam as a rival religion. As Frassetto puts it, this religious stereotyping and "othering" results in an image of Muslims as "enemies of the Christian faith who were included in a global conspiracy with Jews and other servants of the Antichrist and the Devil to destroy Christianity" (140). Such an image invited more violent interaction between Christians and Muslims.

One illustration of that more violent interaction plays out in the Reconquista of Spain (chap. 6). In his discussion of the Reconquista, Frassetto briefly describes the impact of Christian rule on the Mudejar population and on the daily lives of Mudejar communities in Spain. This provides a passing but welcome glimpse into Christian-Muslim relations on the ground, as it were. Again using Spain as a model for the wider experience, in this chapter, Frassetto argues that "[t]he Reconquista was characterized by the patterns of conflict and cooperation that marked Muslim-Christian relations throughout the Middle Ages" (166). As an example of "cooperation" or at least of cultural exchange, Frassetto mentions the alleged influence of Islamic muwashshaha poetry on Provencal troubadour poetry--a subject explored in greater depth by María Rosa Menocal.

The often misunderstood term jihad figures occasionally throughout this book, but is especially prominent in chapter 7 where the topic is crusade and counter-crusade. In keeping with his recurrent argument, Frassetto places holy war in apocalyptic or eschatological context whereby these military encounters took on cosmological significance. Importantly, in his treatment of holy war, Frassetto includes--to an extent perhaps greater than elsewhere in the book--Muslim perspectives on the crusades and on the meaning of jihad. Although Christian authors predominate in this book, here Muslim voices also come to the fore.

Frassetto's argument that Muslim-Christian relations cut in paradoxical or ambivalent directions continues in his treatment of the twelfth-century "renaissance" (chap. 8). As he notes, in the twelfth century Western Christians sharpened their study of Islam and intensified their critique of the Prophet and the Qur'an, but at the same time they also benefitted greatly from "Muslim-sponsored translations and Muslim commentaries on ancient Greek learning" (224). In this chapter, Frassetto discusses not only important theological and philological works (e.g., Petrus Alfonsi, Peter the Venerable, the Toledan Collection) but also the more popular chansons de geste. An especially important implication of this discussion is Frassetto's recognition that anti-Muslim polemic was often intended to define and bolster Christians and Christianity. Here, we see clearly how defining the "other" is largely an exercise in constructing the "self."

By the time we arrive at the thirteenth century (chap. 9), Frassetto's principal arguments or interpretative themes are familiar and well-established. With the rise of the mendicant orders we see an emphasis on missions as an alternative to crusade, although calls for both continued beyond the thirteenth century. For Frassetto, the thirteenth century represents "the final stage of the development of the long history of the relationship between Christians and Muslims in the Middle Ages as long-standing trends come to a close and foundations for new patterns of discussion were set" (253). This statement might suggest less continuity between medieval images and subsequent images of Islam in the West than one finds in, say, Daniel or Tolan. However, Frassetto himself (262) acknowledges this continuity in the early modern and even modern periods.

The book concludes with a brief summary of its main themes and with a useful bibliography of primary and secondary sources. Given the attention Frassetto devotes to Spain in his study, one might expect some inclusion of Spanish language scholarship in the bibliography (there isn't any), but in fact he includes very few non-English language sources, which perhaps suggests something about his intended audience.

Reviewing the primary sources and reflecting on the analysis, it is clear that Frassetto has focused mainly, and perhaps inevitably, on theological works, chronicles, and, to some extent, literary works. He does not include legal texts (e.g., Las Siete Partidas) which might tell a somewhat different story or which might at least emphasize different aspects of the relations between medieval Christians and Muslims. Similarly, some readers might be surprised that important figures such as Mark of Toledo or Riccoldo da Monte di Croce do not appear in Frassetto's narrative. But these criticisms (if that is what they are) only return us to Frassetto's stated aim of "complementing and supplementing"--not replacing--the work of other scholars. Students and perhaps even specialists will find this an informative and nuanced survey of a rich and complex relationship that continues to matter in the twenty-first century.

One final note: the editing of this volume is not always as ideal as one might wish. For example, primary source titles are unevenly italicized throughout the text. This is admittedly minor, but it is noticeable.