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The Fourth Crusade and Its Aftermath (1204)

Why did the Fourth Crusade sack Constantinople (1204) in 1204?

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On this page
  1. The Origins of the Fourth Crusade
  2. The Sack of Constantinople
  3. The Latin Empire
  4. The Aftermath of the Fourth Crusade
  5. Sources
  6. Related Articles

The Fourth Crusade (1202–1204) was the most controversial of all the medieval Crusades. Called by Pope Innocent III in 1198 to recover Jerusalem from Muslim rule, the Crusade was diverted from its original purpose by a complex series of political and financial maneuvers, and it ended in the Sack of Constantinople, a Latin Christian city sacked by fellow Christians. The Sack of Constantinople was a major trauma for the Byzantine world, and it permanently weakened the Byzantine Empire. The Latin Empire of Constantinople that was established lasted less than sixty years, and the trauma of the Sack continues to shape the relations between the Eastern and Western Churches to the present day.

This cluster explores the Fourth Crusade and its aftermath. The articles in the related long-tail pages provide deeper examinations of specific aspects of the topic.

Jonathan Phillips, “The Fourth Crusade and the Sack of Constantinople” (2004), is the standard one-volume treatment. Steven Runciman, “A History of the Crusades,” vol. 3 (1954), is the older and still readable narrative. The page below uses both, and the contemporary accounts (Geoffrey of Villehardouin, the Devastatio Constantinopolitana, the Historia of Nicetas Choniates) as primary material. The question of why the Crusade was diverted is still debated; the page flags the two main readings.

The Origins of the Fourth Crusade

The Fourth Crusade was proclaimed by Pope Innocent III in 1198, shortly after his accession to the papacy. The pope was determined to launch a new Crusade to recover Jerusalem, which had been captured by Saladin in 1187, and he appointed a number of preachers to promote the Crusade across Christendom. The response was initially modest, and the pope had difficulty persuading the major rulers of Europe to take the cross.

The leadership of the Crusade was eventually assumed by Boniface of Montferrat (c. 1165–1207), a northern Italian noble who had family connections to the Byzantine imperial family. The Crusaders needed transport across the Mediterranean, and they signed a contract with the Republic of Venice in 1201, agreeing to pay a large sum of money for the use of Venetian ships. The Venetians, under the leadership of the doge Enrico Dandolo (c. 1107–1205), agreed to transport the Crusaders to Egypt, the center of Ayyubid power, in return for payment.

The financial arrangement collapsed in 1202, when the Crusaders were unable to pay the full sum promised to Venice. The Venetians, who had incurred enormous expenses in building the fleet, insisted on payment and imposed alternative arrangements on the Crusaders. The first major deviation occurred in November 1202, when the Crusaders agreed to attack the Christian city of Zara (now Zadar in Croatia) on behalf of Venice, which had a commercial rival there. The Sack of Zara was a major embarrassment to the papacy, and Pope Innocent excommunicated the entire Crusade.

The Crusade was further diverted in 1203, when Alexios IV Angelos, the son of the deposed Byzantine emperor Isaac II Angelos, arrived at the Crusader camp and promised large rewards if the Crusaders would help him regain the Byzantine throne. The Crusaders agreed, and they sailed to Constantinople, where they installed Alexios IV as co-emperor in August 1203. The new emperor was unable to fulfill his promises, however, and a palace coup in January 1204 overthrew him and installed a new emperor, Alexios V Doukas.

The Sack of Constantinople

The Sack of Constantinople began on April 12, 1204, and lasted for three days. The Crusaders stormed the walls of the city and broke through the defenses, and they proceeded to pillage the city in a systematic and brutal fashion. The chroniclers of the Sack — including the eyewitness account of Geoffrey of Villehardouin and the later account of Niketas Choniates — describe the massacre of the inhabitants, the rape of the women, the looting of the churches and palaces, and the destruction of the art and literature of the Byzantine world.

The Sack of Constantinople was a major trauma for the Byzantine world and for Christendom as a whole. The Byzantine Empire was permanently weakened, and the Byzantine state was never fully restored. The library of Constantinople, with its priceless collection of manuscripts of classical Greek literature, was partially destroyed, and many treasures of Byzantine art were lost or carried off to Western Europe. The relations between the Eastern and Western Churches were permanently damaged, and the schism that had existed since the eleventh century was deepened and entrenched.

The Sack of Constantinople was justified by some Western apologists as a punishment for the Byzantines’ refusal to submit to the papacy and as a necessary step toward the reunification of the Churches. The most notorious of the apologists was the Crusader cleric Robert of Clari, who described the Sack as a glorious event that demonstrated the will of God. The Byzantine view of the Sack was markedly different: Niketas Choniates, the leading Byzantine historian of the period, described the Sack as a catastrophe of unprecedented proportions, and he blamed the Crusaders for the destruction of Christian civilization.

The Latin Empire

The Crusaders established a Latin Empire in Constantinople after the Sack, with Baldwin of Flanders as the first Latin emperor. The Latin Empire claimed sovereignty over the Byzantine territories in Greece, Asia Minor, and the Aegean, and it allocated the Byzantine territories among the Crusader leaders. The Venetians received major territorial concessions, including Crete, parts of the Peloponnese, and the important port of Galata across the Golden Horn from Constantinople.

The Latin Empire was immediately challenged by Byzantine successor states that emerged in the wake of the Sack. The Empire of Nicaea, founded by the Byzantine imperial family in Asia Minor, gradually consolidated its control over the rump of the Byzantine world and eventually recaptured Constantinople in 1261, ending the Latin Empire. The Despotate of Epirus, founded by another branch of the Byzantine family in northwestern Greece, competed with Nicaea for the succession of the Byzantine Empire. The successor states of Trebizond, in northern Asia Minor, and of Cyprus, ruled by the Lusignan family, maintained a degree of autonomy for several centuries.

The Latin Empire was a precarious state from the outset. The Crusaders were a small minority in a vast and hostile empire, and they depended on support from Western Europe to maintain their position. The loss of the Crusader stronghold at Antioch in 1268, shortly after the collapse of the Latin Empire, symbolized the decline of the Latin presence in the East.

The Aftermath of the Fourth Crusade

The aftermath of the Fourth Crusade was far-reaching. The trauma of the Sack deepened the schism between the Eastern and Western Churches, and it contributed to the decline of the Byzantine Empire that eventually led to the fall of Constantinople to the Ottoman Turks in 1453. The Ottoman conquest of Constantinople was a major event in the history of Christianity and Islam, and it marked the end of the Byzantine Empire and the beginning of the Ottoman hegemony in the eastern Mediterranean.

The Fourth Crusade also had a major impact on the Crusading movement itself. The Sack of Constantinople discredited the Crusade as an institution, and it contributed to the decline of the Crusading ideal in the fourteenth and fifteenth centuries. The later Crusades — the Fifth Crusade (1217–1221), the Sixth Crusade (1228–1229), the Seventh Crusade (1248–1254), and the Eighth Crusade (1270) — were all marked by the decline of Crusader enthusiasm and the growing strength of the Muslim states of the Near East.

The Fourth Crusade also had a major impact on the economy and culture of the Mediterranean. The Venetian Empire expanded enormously as a result of the Sack, gaining major territorial and commercial concessions in Greece and the Aegean. The Venetian presence in the eastern Mediterranean lasted until the sixteenth century, and it played a major role in the cultural exchange between Western and Eastern Europe. The Fourth Crusade also contributed to the transmission of Byzantine art and learning to the West, laying the foundations for the Renaissance of the fifteenth and sixteenth centuries.

Sources

Principal sources used in this article:

Further reading:

For a recent single-volume synthesis with full scholarly apparatus, see the relevant chapter of Barbara H. Rosenwein, A Short History of the Middle Ages (University of Toronto Press, 2014).