In The Prester John Legend Between East and West During the Crusades: Entangled Eastern-Latin Mythical Legacies, Ahmed Sheir offers two theses. The first challenges Eurocentric interpretations of the Prester John legend through a meticulous uncovering of the Eastern Christian components of the story. Second, he argues that the legend itself had a hand in shaping inter-European politics and the course of the Crusades during the twelfth and thirteenth centuries. This study is grounded in analysis of Arabic, Coptic, and Syriac, as well as Latin, sources.

According to stories that spread across Europe beginning in the twelfth century at the time of the Crusades, Prester John was a mythical Christian king who ruled over a fabled Christian empire in the East. This “East” was variously located in India, Central Asia, and Ethiopia. These stories persisted into the early modern period. Until the 1980s, scholars focused on the literary and philological aspects of two extant sources that mention Prester John, Otto of Freising's (d. 1158 CE) universal history, The Two Cities, and the Prester John Letter, a manufactured letter addressed by Prester John to Byzantine Emperor Manuel Komnenus and composed between 1165 and 1170 CE. Historians also tended to prioritize a later, early modern Ethiopian version of Prester John over his twelfth- and thirteenth-century Asian personas. Recently, scholars have deepened our knowledge of the broader historical significance of these and other sources that touch on the Prester John legend. They have been used as sources for conceptualizing medieval European notions of alterity as well as contextualizing the European encounter with Asia and East Africa from the early Middle Ages to the seventeenth century.

Sheir argues that despite these advances, the Arab and more broadly Eastern roots and consequences of the legend have yet to be fully explored. His book presents a “transcultural and entangled history of the legend. . . from its Eastern Christian core in late antiquity down to [its] Latinized and crusading form. . . [in] the twelfth and thirteenth centuries” (33). Sheir delivers a critical and nuanced reading of a mass of sources in Arabic, Coptic, and Syriac, in addition to Latin.

From its origin story to final defeat of Latin kingdoms in the Levant, Western myths entangled with Eastern imaginaries to produce a transcultural version of Prester John. Well before the advent of Prester John, the idea of a priest king lording over a Christian utopia in India circulated among Eastern Christians. Confrontations between Eastern Christians and non-Christian empires to the east, first Sassanian and then Muslim, fueled apocalyptic visions assuaged by anticipation of a savior king. The apocryphal story of the Apostle Thomas’ evangelizing mission to India was originally written in Syriac before being translated into Greek and then Latin. The Acts of St Thomas may have been written in Edessa, the center of Syrian Christianity (71). The legend of King Abgar, who was said to have been appointed by Jesus to protect the Christians of Edessa, was also originally written in Syriac (86–87). It was the fall of Edessa to Muslim forces in 1144 CE that gave birth to the Prester John legend. “By drawing parallels between the legendary King Agbar, St. Thomas, and the Christians of Edessa, a common belief was produced among the Franks and Christian inhabitants of Edessa, who were mainly Armenians and Syrians, that the promise of Jesus Christ protected them” (87–88). The first mention of Prester John comes in the aftermath of the Latin loss of Edessa.

The fall of Edessa sparked belief in a Christian “rescuer” coming from the east. Seljuk Muslim rulers did suffer a defeat in 1141 CE at the hands of Khitan forces in Qatwan, near Samarkand. Sheir refers to the accounts of Muslim historians Ibn al-Athir (d. 1232 CE) and Ibn al-Jawzi (d. 1201 CE) to document how devastating this loss was for Muslims, marking the beginning of the end of the Great Seljuk empire. The news reached the Franks, but in the Christian (both Western and Eastern) imaginings of the time, the Khitan were wrongly identified as Nestorian Christians led by Prester John intent on rescuing their co-religionists to the west.

Another phase in this history of entangled Eastern and Western legends appears two decades later in the Prester John Letter. The letter depicts a mythical eastern paradise that draws from the Syriac versions of the Alexander Romance, a mostly fictional account of the life and times of Alexander the Great, which was at turns Christianized and Islamized. The ancient Greek geographical knowledge that informed the descriptions of the Prester John's “Indian” paradise arrived in Europe through Arabic translations. The twelfth-century Muslim cartographer al-Idrisi's (d. 1165 CE) descriptions reveal “several similarities between the imaginary conception of the Prester John kingdom in India and the Arabo-Muslim imagination about India and the Far East” (172).

These are just a few examples of a mass of detail from sources in Arabic, Coptic, Syriac, and Latin that Sheir uncovers to advance the thesis that the Crusades were a “trans-Mediterranean phenomena that could not be understood without considering various Latin-Arab and Christian-Muslim transcultural views” (30–31).

Sheir also asserts that the Prester John legend was not just a matter of mythmaking but had material effects on the course of the Crusades and inter-European politics. It served as propaganda to whip up support in Europe for the Crusades once Muslims rolled back Latin gains in the Levant. The Prester John Letter figures in the conflict between the Emperor Frederick and the Pope Alexander III between 1154 and 1177 CE. In the case of the Fifth Crusade (1217–1221 CE) to Egypt, a version of the legend (derived from earlier Coptic sources) involving Prester John's son, an Ethiopian King David, led to a military disaster. Crusader forces made the fatal error of rejecting an Ayyubid peace proposal in anticipation of a non-existent King David coming to their rescue from the south. Sheir's arguments for the role of the legend on the politics of the Church and on the course of the Crusades are convincing though their connection to the cross-cultural roots of the legend is less clear.

Ahmed Sheir convincingly demonstrates the transcultural nature of the Prester John legend. The Prester John Legend Between East and West During the Crusades presents a welcome corrective to Eurocentric interpretations of medieval Mediterranean history by placing the period of the Crusades within its proper global historical context.