For too long, the history of Carolingian diplomatic relations with the Islamic world has been written largely based on the Latin sources, and the Christian–Muslim encounter has too often been filtered through the distorting lenses of the crusades and the mythic Carolingian world of the chansons de geste. Enduring yet contradictory narratives have either held that Charlemagne had fully dedicated himself to driving the Muslims out of Europe or that he was a tolerant promoter of a multicultural empire. With The Emperor and the Elephant: Christians and Muslims in the Age of Charlemagne Sam Ottewill-Soulsby set out to dispel both of these myths, and the result is a learned and engagingly written book. By using both Latin and Arabic sources and integrating, to the extent possible, the perspectives of those on both sides of a century of diplomatic exchanges, Ottewill-Soulsby succeeds in producing a much fuller and more nuanced picture of Muslim–Christian relations in the Carolingian era than any we have seen before.

Ottewill-Soulsby's integration of the sources for the Abbasid and Umayyad dynasties into the history of Carolingian diplomatic relations with their Muslim counterparts, both to the east and in Al-Andalus, allows him to develop a convincing argument for the existence of two distinct styles of diplomacy. The first is exemplified by the relationship between Charlemagne and the Abbasid Caliph Harun-al-Rachid, famous for his gift of the elephant Abu al Abbas that arrived at Aachen in 802, a style that he calls “prestige diplomacy.” This brand of diplomatic activity was carried out largely to impress local elites, offering tangible evidence of a ruler's healthy reputation abroad. These exchanges were not necessarily practical, as the transport of an elephant over thousands of miles suggests, but they played an important role both in the self-presentation of the ruler and in his depiction by historians of the realm. We are still talking about Harun's majestic gift this many centuries later. Prestige diplomacy was also episodic and tended to occur between stable regimes. The Islamic sources reflect similar symbolic importance attributed to the Frankish gifts received at the Abbasid court. Elephants were meaningful for both, and Harun's gift represented a point of common meaning understood by both participants.

The second style of diplomacy applies to the complex diplomatic relations between the Latin West and the Umayyad caliphate in Al-Andalus, which Ottewill-Soulsby calls “frontier diplomacy.” The fraught and often hostile relationships between the Franks and the leadership at Córdoba were part of a complex geographical picture that included the two buffer zones known as the Upper March, part of Al-Andalus up to the Ebro River, and the Spanish March, which extended from the Ebro to the Pyrenees. The marches housed various political entities, both Christian and Muslim, that together constituted a large intermediate zone that separated the Caliphate and the West Frankish kingdom. Both marches were multiethnic, with Goths and Basques prominent in both, as well as Frankish, Arab, and Berber settlers. The Spanish March included, among other places, Pamplona, the county of Aragon, and the cities of Girona and Barcelona, which were controlled by a powerful count. The Umayyad leadership generally left the management of the Upper March to urban governors, often the descendants of elite Arab settlers, some powerful enough to raise their own armies.

Whereas prestige diplomacy was largely voluntary between the distant Abbasid and Carolingian seats of power, diplomacy between the Franks and the powerful caliphate to the south occurred out of necessity, since only the unpredictable marches separated the two powers. Ottewill-Soulsby effectively refutes the too-common assumption that the histories of the two realms rarely impinged upon one another, with Roncesvalles in 778 as the famous exception. Carolingian Europe was not isolated from Muslim Spain after 711, as has often been assumed. The opposite was true, as The Emperor and the Elephant demonstrates again and again through the author's inclusion of the Umayyads in the history of Carolingian Catalonia.

Ottewill-Soulsby succeeds in his stated goal of rescuing the Muslims from functioning as merely part of the landscape of the Carolingian past. One of the book's major strengths is its readability thanks to the author's confident command of the material and talent for narrating complex events from multiple perspectives. Moments such as the ambush in the Pyrenees in 778 or the multiple crises in the reign of Louis the Pious take on new dimensions when the Latin sources are reread against the Arabic sources and then productively reframed. The reign of Louis the Pious saw intense conflict with Al-Andalus in the late 820s, the failed management of which, as Ottewill-Soulsby argues, contributed more than has previously been acknowledged to the crisis of his reign in 833 with the rebellion of his sons. Louis had engaged in far less diplomatic activity with the Muslim world than had his father, while the reign of Louis's son, Charles the Bald marked the end of Carolingian–Umayyad relations in 831. Those with the rest of the Islamic world also appear to have ended for the Carolingians in 831.

Ottewill-Soulsby brings this impressive study to an end with the image of Charlemagne's body wrapped in a silk shroud decorated with images of elephants, the emperor like his memory forever intertwined with the symbol of his friendly diplomatic relations with the Abbasid caliph. This groundbreaking and much-needed new study will be a required reference for all future scholarly considerations of the early medieval world.