The main topic of Stephen O’Shea’s book, Sea of Faith: Islam and Christianity in the Medieval Mediterranean World, is the first millennium of interaction between Christianity and Islam following the rise of Islam in the seventh century.The book specifically explores this “shared history” through two primary, alternating lenses:
- Epochal Conflict: O’Shea uses seven major battles as turning points to illustrate the military struggle for spiritual and political primacy around the Mediterranean. These include:
- Yarmuk (636): The rise of Islam and the fall of Christian Syria and Palestine.
- Poitiers (732): The end of the initial century of Arab conquest in Europe.
- Manzikert (1071): The fall of Christian Anatolia to the Turks.
- Hattin (1187): The era of the Crusades and the fall of the Latin Kingdom of Jerusalem.
- Las Navas de Tolosa (1212): The decisive blow to Muslim rule in al-Andalus (Spain).
- Constantinople (1453): The fall of the Byzantine Empire to the Ottoman Turks.
- Malta (1565): The final major military standoff of the medieval era.
- Coexistence and Exchange (Convivencia): Counterbalancing the violence, the book details long periods of “living together” and mutual enrichment. It highlights centers of cultural and intellectual commingling, such as Umayyad Córdoba, Norman Palermo, Christian Toledo, and Ottoman Kostantiniyye (Constantinople).
Ultimately, O’Shea frames the competition between these two faiths—both sprung from the same Abrahamic source—as a “sibling rivalry writ very large” over the inheritance of the Greco-Roman Mediterranean world.
The author, Stephen O’Shea, uses the following seven battles to frame the thousand-year military conflict between Islam and Christianity:
- Yarmuk (636): Marked the fall of Christian Syria and Palestine to the rising forces of Islam.
- Poitiers (732): Represented the end of an initial century of Arab conquest following the death of Muhammad.
- Manzikert (1071): Signaled the fall of Christian Anatolia to the Turks.
- Hattin (1187): A decisive victory for Saladin that led to the fall of the Latin Kingdom of Jerusalem and the doom of Outremer.
- Las Navas de Tolosa (1212): Viewed as a “deathblow” to Muslim rule in al-Andalus (Spain).
- Constantinople (1453): The final fall of the Byzantine Empire’s capital to the Ottoman Turks.
- Malta (1565): A failure for the Ottomans that marked the end of the medieval “sea of faith”.
This book by Stephen O’Shea explores the first millennium of interaction between Christianity and Islam in the Mediterranean through a series of key battles and periods of cultural exchange.
Chapter 1: Yarmuk 636
- The Rise of Islam: This chapter traces the life of Muhammad, from his first revelations in 610 to his death in 632, by which time he had unified much of the Arabian peninsula under Islam.
- The Battle: In 636, at the Yarmuk River, Arab Muslim forces under commanders like Khalid Ibn al-Walid decisively defeated the Byzantine army led by Emperor Heraclius.
- Consequences: This victory led to the fall of Christian Syria and Palestine, ending Byzantine hegemony in the region and making way for the Islamic Caliphate.
Chapter 2: Poitiers 732
- Arab Expansion: Following Yarmuk, Muslim conquests rapidly expanded across Egypt, North Africa, and finally into Spain by 711.
- The Clash in Gaul: Led by Abd al-Rahman al-Ghafiqi, Muslim forces crossed the Pyrenees and advanced deep into France until they were met by Charles Martel and his Frankish army.
- Turning Point: The Frankish victory at Poitiers in 732 brought the century of initial Arab expansion to a halt in Western Europe.
Chapter 3: Córdoba
- The Umayyad Refuge: After the Abbasid revolution in the east, the Umayyad prince Abd al-Rahman I fled to Spain and established an independent emirate centered in Córdoba in 756.
- Convivencia: Under the Umayyads, Córdoba became the most advanced city in Western Europe, characterized by convivencia—a productive coexistence between Muslims, Christians, and Jews.
- Cultural Zenith: This “Golden Age” featured immense libraries, agricultural innovations, and a vibrant culture of poetry and science that later influenced all of Europe.
Chapter 4: Manzikert 1071
- The Turkic Incursion: In the 11th century, Seljuk Turks rose to power in the Middle East, replacing Arab political dominance and threatening the Byzantine heartland in Anatolia.
- Byzantine Defeat: Internal court intrigues and military mismanagement in Constantinople led to a crushing defeat for Emperor Romanus IV Diogenes against Sultan Alp Arslan at Manzikert.
- Long-term Impact: The battle opened the “Gateway to Anatolia” for Turkic settlement, permanently altering the region’s religious and ethnic identity and helping spark the Crusades.
Chapter 5: Palermo and Toledo
- Norman Sicily: Normans captured Palermo from its Muslim emirs in 1072, yet King Roger II continued the Islamic tradition of tolerance, creating a cosmopolitan hub of Arab, Greek, and Latin scholarship.
- The Fall of Toledo: In 1085, the Castilian king Alfonso VI took Toledo, which then became a primary site for translating Arabic versions of ancient Greek philosophy and science into Latin.
- The First Crusade: Amid these examples of convivencia, Pope Urban II called for a holy war in 1095, leading to the brutal 1099 sack of Jerusalem and the establishment of “Outremer” (crusader states).
Chapter 6: Hattin 1187
- Muslim Unity: After decades of division, the Muslim Near East was unified under Saladin, who rallied his forces through the ideology of jihad.
- Decisive Battle: In 1187, at the Horns of Hattin, Saladin’s forces trapped the thirsty crusader army, leading to the capture of King Guy of Jerusalem and the execution of the notorious Reynaud of Châtillon.
- Recapture of Jerusalem: Following Hattin, Saladin quickly reclaimed Jerusalem for Islam, though he was noted for showing relative magnanimity toward the defeated Christians.
Chapter 7: Las Navas de Tolosa 1212
- Almohad Challenge: A new Berber dynasty, the Almohads, crossed from North Africa to reunite al-Andalus and challenge the growing power of the Christian kingdoms.
- Crusader Alliance: Under the guidance of Pope Innocent III, the long-quarrelsome kings of Castile, Aragon, and Navarre united their forces to launch a decisive offensive against the Muslims.
- The Deathblow: The Christian victory at Las Navas de Tolosa in 1212 broke Almohad power and doomed al-Andalus to a slow retreat, culminating in the 1492 fall of Granada.
Chapter 8: The Sea of Faith
- A World of Exchange: During the 13th and 14th centuries, despite ongoing conflicts, the Mediterranean saw a vast increase in commercial and cultural exchange mediated by Italian merchants and religious missionaries like Francis of Assisi.
- Mongol Impact: The 1258 Mongol sack of Baghdad destroyed the Abbasid Caliphate, shifting the centers of Islamic power to the Mamluks in Egypt and the emerging Turks.
- Ottoman Rise: An obscure Turkish clan, the Ottomans, established a bridgehead at Gallipoli in 1354 and began a rapid expansion into the Balkans.
Chapter 9: Constantinople 1453 and Kostantiniyye
- The Final Siege: Sultan Mehmet II, “the Conqueror,” launched a massive assault on the last remnants of the Byzantine Empire in 1453, using revolutionary heavy cannons to breach the legendary walls.
- Fall of New Rome: After 53 days, the city fell, Constantine XI died in the fighting, and the Hagia Sophia was converted into a mosque.
- New Coexistence: Mehmet rebuilt the city as Kostantiniyye, inviting Greeks, Armenians, and Jews (including those later expelled from Spain) to settle there, creating a final major era of Mediterranean convivencia.
Chapter 10: Malta 1565
- The Last Stand: The Knights of St. John, based on Malta, became the final frontier for militant Christianity against the Ottoman armada of Mustapha Pasha and the pirate Dragut Rais.
- Brutal Siege: The four-month conflict was marked by extreme atrocities on both sides, including the decapitation of prisoners and dead soldiers.
- End of an Era: The successful defense of Malta in 1565 checked Ottoman expansion and signaled the end of the medieval era of the “sea of faith,” as European interests shifted toward the Atlantic.
Stephen O’Shea’s Sea of Faith examines the first millennium of interaction between Islam and Christianity (from the seventh to the sixteenth centuries) through the dual lens of epochal military conflict and cultural coexistence (convivencia).
Framework of Analysis
The author structures his analysis of this “shared history” by alternating between two main historical modes:
- Military Turning Points: O’Shea uses seven decisive battles to frame the struggle for political and spiritual primacy around the Mediterranean:
- Yarmuk (636): The fall of Christian Syria/Palestine.
- Poitiers (732): The end of initial Arab expansion into Europe.
- Manzikert (1071): The loss of Christian Anatolia to the Turks.
- Hattin (1187): The recapture of Jerusalem by Saladin.
- Las Navas de Tolosa (1212): The decisive blow to Muslim al-Andalus.
- Constantinople (1453): The fall of the Byzantine Empire to the Ottomans.
- Malta (1565): The final standoff of the medieval “sea of faith”.
- Centers of Convivencia: To counterbalance the narrative of violence, O’Shea details long periods of “living together” and intellectual exchange in major cosmopolitan hubs:
- Umayyad Córdoba: A “Golden Age” of arts, sciences, and religious tolerance.
- Norman Palermo: A multilingual center where Arab, Greek, and Latin scholarship converged.
- Christian Toledo: A vital site for translating Arabic knowledge (including lost Greek philosophy) into Latin.
- Ottoman Kostantiniyye: A multicultural capital that welcomed diverse faiths following the 1453 conquest.
Major Themes and Conclusions
- Sibling Rivalry: O’Shea frames the relationship as a “sibling rivalry writ very large” over the Greco-Roman inheritance. Both faiths sprang from the same Abrahamic source, yet often viewed each other through a lens of mutual ignorance or as a “heretical” deviation from their own truth.
- Confessional Geography: The book argues that the modern religious identities of Mediterranean countries (e.g., Muslim Turkey vs. Christian Spain) were not inevitable but were determined by the “contingencies of battle and the actions of men” during this period.
- Impact of Belief on Statecraft: While religion provided “respectable cover” for worldly greed and ambition, it profoundly influenced law, language, and the organizing principles of these societies.
- End of an Era: By the late sixteenth century, the Mediterranean ceased to be primarily a “sea of faith” as commercial interests and the rise of the Atlantic powers signaled the dawn of the early modern period.