The Fourth Crusade (1202–1204), originally designed to conquer Jerusalem by taking Egypt first, instead, in 1204, conquered and sacked the Orthodox Christian city of Constantinople, capital of the Byzantine Empire.
After the failure of the Third Crusade, there was little interest in Europe for another crusade against the Muslims. The Fourth Crusade was the last of the major crusades to be directed by the Papacy, before the Popes lost much of their power to the Holy Roman Empire and other secular monarchs. The later crusades were directed by individual monarchs, and even the Fourth quickly fell out of Papal control.
In 1198, Pope Innocent III called for a new Crusade, which was largely ignored among European leaders. The Germans were struggling against Papal power, and England and France were still engaged in warfare against each other. However, due to the preaching of Fulk of Neuilly, a crusading army was finally organized at a tournament held at Ecry by Count Thibaud of Champagne in 1199. Thibaud was elected leader, but he died in 1200 and was replaced by an Italian count, Boniface of Montferrat. Boniface and the other leaders sent envoys to Venice, Genoa, and other city-states to negotiate a contract for transportation to Egypt, the object of their crusade; one of the envoys was the historian Geoffrey of Villehardouin. Genoa was uninterested but Venice agreed to transport 33,500 crusaders (as well as 4,500 horses), a very ambitious number. This agreement required a full year of preparation on the part of the city of Venice to build numerous ships and train the sailors that would man them, all the while curtailing the city's commercial activities.
Attack on Zara
Since there was no binding agreement amongst the crusaders that all should sail from Venice, many chose to sail from other ports, particularly Flanders, Marseilles and Genoa. By 1201 the crusader army was collected at Venice, though with far fewer troops than expected. The Venetians, under the aged and possibly blind doge Enrico Dandolo, would not let the crusaders leave without being paid the full amount agreed to originally of 85,000 silver marks, but the crusaders could only pay some 51,000, and that only by reducing themselves to extreme poverty. The Venetians barricaded them on the island of Lido until they could decide what to do with them.
Dandolo and the Venetians succeeded in turning the crusading movement to their own purposes. Dandolo, who made a very public show of joining the crusade during a ceremony in the church of San Marco di Venezia, proposed that the crusaders could pay their debts by attacking the port of Zara in Dalmatia (essentially an independent community which recognized King Emeric of Hungary as a protector, and which was previously ruled by Venice; now Zadar in Croatia). The Hungarian king Emeric was Catholic and had himself "taken the cross", meaning he too had agreed to join the crusade (though this was mostly for political reasons). Many of the crusaders were opposed to this, and some, including a force led by the elder Simon de Montfort, refused to participate altogether and returned home. While the papal representative to the crusade, Peter Cardinal Capuano, endorsed the move as necessary to prevent the crusade's complete failure, pope Innocent was alarmed at this development and wrote a letter to the crusade leadership threatening excommunication; this letter was concealed from the bulk of the army and the attack proceeded. The citizens of Zara made reference to the fact that they were fellow Catholics by hanging banners marked with crosses from their windows and the walls of the city, but nevertheless the city fell after a brief siege. Both the Venetians and the crusaders were immediately excommunicated for this by Innocent III.
Diversion to Constantinople
Boniface, meanwhile, had left the fleet before it sailed from Venice, and had visited his cousin Philip of Swabia. The reasons for his visit are a matter of debate; he may have realized the Venetians' plans and left to avoid excommunication, or he may have wanted to meet with Byzantine Prince Alexius Angelos, Philip's brother-in-law and the son of the recently deposed Byzantine emperor Isaac II. Alexius had fled to Philip when his father was overthrown in 1195, but it is unknown whether or not Boniface knew he was at Philip's court. In any case, Alexius offered to pay off the Crusaders' debt to Venice, if they would restore his family to the Byzantine throne, an offer Boniface found difficult to refuse. Boniface may also have had in mind the former land holdings of his brother Renier of Montferrat, who had married a daughter of emperor Manuel I Comnenus but had been murdered in a Byzantine faction-struggle in 1183. Alexius returned with Boniface to rejoin the fleet at Corfu after it sailed from Zara, and the Venetians, when they learned of Alexius' idea, were particularly pleased with it. They also had been personally offended by the Byzantines in recent years, as thousands of western Europeans (including many Venetians) had been killed in riots against their merchant communities in Constantinople in 1182.
The Crusaders were still reluctant to attack fellow Christians, but the clergy convinced them that the Orthodox Byzantines were the next best thing to the Muslims. They had allied with Saladin against the Third Crusade, and had done nothing to aid the Second Crusade; they should be punished for their lack of support. Unfortunately for them, Alexius Angelus had overstated his importance and it was quickly discovered when the crusaders arrived at the walls of Constantinople that the citizens preferred an usurper to an emperor supported by the hated "Latins". The crusaders and Venetians decided to place Alexius on the throne by force, and an amphibious assault was launched on the city in 1203. Unexpectedly, emperor Alexius III panicked and fled, and the citizens of Constantinople reluctantly welcomed Alexius Angelus back into the city. He was crowned emperor as Alexius IV, and his father Isaac II was restored as co-emperor.
Further attacks on Constantinople
The crusaders were opposed to Isaac, as they had never met him and did not believe he was part of their deal with Alexius, but the Byzantines did not want Alexius, who was just as unknown to them, to rule by himself. Isaac soon realized that Alexius' promises were impossible to keep, and Alexius was forced to rescind on his bargain as the imperial treasury was empty. Alexius also had to deal with the growing hatred by the citizens of Constantinople for the "Latins" in their midst. Factions opposed to the Latins frequently attacked any crusaders they could find, and Alexius had to tell his allies to leave and set up camp on the other side of the Golden Horn. Nevertheless there was still fighting in the city, and during an attack by the crusaders on a mosque (which they were shocked to find in the Christian city), a large part of Constantinople was burned down. Opposition to Alexius IV grew, and one of his courtiers, Alexius Ducas Murtzuphlos, soon overthrew him and had him strangled to death. Alexius Ducas took the throne himself as Alexius V; Isaac died soon afterwards, probably naturally.
The Crusaders and Venetians, incensed at the murder of their supposed patron, attacked the city once more in 1204. Alexius V, who had a much larger army, although it was much more poorly trained, marched his troops outside Constantinople and seemed to prepare for an all-out assault on the crusader force. As the crusaders panicked and armed everyone they could find, including cooks who wore their pots as helmets, Alexius V turned around and marched his army back into the city. It is possible that his foot soldiers were afraid of the western knights, who had defeated them earlier in the year in skirmishes outside the city, but the actual reason for Alexius' refusal to fight is unknown. Although Innocent III had again warned them not to attack, the papal letter was suppressed by the clergy, and the crusaders prepared for their own attack, while the Venetians attacked from the sea; Alexius' army stayed in the city to fight, along with the imperial bodyguard, the Varangians, but Alexius himself fled during the night.
Final capture of Constantinople; outcome
The crusaders were eventually able to knock holes in the walls, small enough for a few knights at a time to crawl through; the Venetians were also successful at scaling the walls from the sea, though there was extremely bloody fighting with the Varangians. The crusaders captured the Blachernae section of the city in the northwest and used it as a base to attack the rest of the city, but while attempting to defend themselves with a wall of fire, they ended up burning down even more of the city than they had the first time. Eventually, the crusaders were victorious, and the citizens of the city, strangely, at least to western eyes, welcomed them into the city as usurpers, not as conquerors. The crusaders did not see it this way, and they inflicted a horrible and savage sacking on Constantinople for three days, during which many ancient works of art were stolen or destroyed.
According to a pre-arranged treaty, the empire was apportioned between Venice and the Crusade's leaders, and the Latin Empire at Constantinople was established. Boniface was not elected as the new emperor, although the citizens seemed to consider him as such; the Venetians thought he had too many connections with the former empire because of his brother's land holdings, and instead placed Baldwin of Flanders on the throne. Boniface went on to found the Kingdom of Thessalonica, a vassal state of the new Latin Empire. The Venetians also founded the Duchy of the Archipelago in the Aegean Sea. Meanwhile, Byzantine refugees founded their own successor states, the most notable of these being the Empire of Nicaea under Theodore Lascaris, the Empire of Trebizond, and the Despotate of Epirus.
- Nicetas Choniates, The Sack of Constantinople
- Robert of Clari, The Conquest of Constantinople (see also excerpts from another translation)
- The Sack of Constantinople by the Crusaders (excerpts from several contemporary accounts)
- The Fourth Crusade 1204: Collected Sources (excerpts from several contemporary accounts)
- Geoffrey de Villehardouin, Chronicle of The Fourth Crusade and The Conquest of Constantinople
- Pope Innocent III, Reprimand of Papal Legate
- W.B. Bartlett, An Ungodly War: The Sack of Constantinople & the Fourth Crusade. Stroud: Sutton Publishing, 2000.
- Charles Brand, Byzantium Confronts the West, 1180-1204, ISBN 0751200530
- Nicholas A. Cooke, "The Sack of Constantinople." 2000
- John Godfrey, 1204: The Unholy Crusade. Oxford: Oxford University Press, 1980.
- Ralph-Johannes Lilie, Byzantium and the Crusader States, 1096-1204, trans. by J.C. Morris and Jean E. Ridings. Oxford: Clarendon Press, 1993; orig. pub. 1988.
- Serban Marin, A Humanist Vision regarding the Fourth Crusade and the State of the Assenides. The Chronicle of Paul Ramusio (Paulus Rhamnusius), Annuario. Istituto Romeno di Cultura e Ricerca Umanistica v. 2 (2000): 51-57
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- Donald E. Queller, The Latin Conquest of Constantinople, New York, London, Sydney, Toronto: John Wiley and Sons, Inc., 1971
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