Reviewed by: Conversion, Circumcision, and Ritual Murder in Medieval Europe by Paola Tartakoff Sarah Ifft Decker Conversion, Circumcision, and Ritual Murder in Medieval Europe. By Paola Tartakoff. Philadelphia: University of Pennsylvania Press, 2020. In the thirteenth century, Christian Europe felt under attack from both internal and external enemies: heretics, Muslims, Jews. In response to these threats, whether real or imagined, lay and ecclesiastical authorities heightened their efforts to consolidate Christian identity and reinforce boundaries between faiths. Rising anti-Judaism, in particular, reflected anxieties about the potential instability of Christian identity. However, these attempts to construct social and legal separation between Christians and Jews went hand in hand with the constant blurring of lines. The rhetoric of boundary maintenance itself revealed the troubled nature of these boundaries. Conversion, although potentially desirable, highlighted the permeability of the borders between faiths. Power dynamics in medieval Europe meant that, in theory, conversion should occur in only one direction: toward Christianity. But reality was messier than theory. A small number of born Christians converted to Judaism; Jewish converts reverted to their former faith; liminal individuals occupied the interstices between Judaism and Christianity. In Conversion, Circumcision, and Ritual Murder in Medieval Europe, Paola Tartakoff offers a nuanced exploration of how Christians and Jews thought about these compelling yet dangerous movements between faiths. Tartakoff adopts the pioneering approach of intertwining the study of Christian conversion to Judaism with that of Jewish conversion to Christianity, which she describes as “two subjects whose historiographies have passed until now like ships in the night” (9). By exploring conversion as a bidirectional phenomenon, she offers new insight into both the experiences of converts and the multifaceted attitudes of both communities toward conversion. Her careful delineation of the parallels and divergences between converts paints a portrait of religious transformation, change, and fluidity that is at once broadly synthetic and richly detailed. [End Page 231] Tartakoff frames her narrative around a particular case study, an unusual situation that is illuminated by the broader context of anti-Judaism and multidirectional conversion in thirteenth-century Europe. In 1144, the Jews of Norwich had weathered the earliest recorded ritual murder accusation: they were charged with the murder of a Christian boy named William. Then, nearly a century later, in 1231, a group of Jews from the same city were accused of kidnapping and forcibly circumcising a Christian child named Edward, with the goal of making him a Jew. The story of Edward intersects in striking ways with false anti-Jewish accusations of ritual murder and host desecration, on the one hand, and Christian forcible conversions of Jewish children, on the other. Tartakoff contextualizes Edward’s story by placing it in conversation with discourses of anti-Judaism, Jewish and Christian attitudes toward conversion, and the lived experience of converts. In closing, she offers a speculative yet compelling reading of Edward’s case as a Jewish effort to reclaim a neglected child of contested religious status. The author begins the book by addressing thirteenth-century Christians’ renewed anxieties that Judaism was attractive to Christians and that Jews were actively seeking to lure Christians from their faith. These fears reflected broader concerns about the instability of Christian religious identity. Such concerns went beyond Judaism: the prevalence of Christian heresy and the reports of Christian apostasy to Islam disquieted church leadership. Ecclesiastical writers portrayed Christendom as under attack from diverse forces of spiritual corruption, forces that at times became blended into a single enemy. The Norwich circumcision case both highlighted and reinforced these anxieties. Tartakoff then investigates the link between fears of Christian apostasy and other manifestations of a multivalent Christian anti-Judaism. The thirteenth century witnessed the consolidation of discourses of anti-Judaism that cast Jews (in reality, a vulnerable minority) as powerful enemies bent on the destruction of Christendom and the suffering of Christians. The allegations of ritual murder and host desecration that plagued Jewish communities in the twelfth and thirteenth centuries framed Jews as dangers to present-day Christendom because they were deliberately working to reenact their past murder of Christ. Tartakoff focuses here on the motif of circumcision, central to the accusation levied against the Norwich Jews in the 1230s. Circumcision functioned as the sole aspect...