The Crusade That Sacked Christendom's Greatest City

The fleet that gathered in the Venetian lagoon in the spring of 1202 was the largest amphibious force the medieval West had ever assembled. More than 200 vessels — war galleys, horse transports, and supply ships — waited for an army of French and Flemish knights who had taken the cross to reclaim Jerusalem from Muslim rule. Their contract with the Republic of Venice was precise: 85,000 marks for transport and provisions for 4,500 knights, 9,000 squires, and 20,000 foot soldiers. But when the crusaders mustered, barely a third of the expected numbers appeared. The treasury was 34,000 marks short.

The Doge of Venice, Enrico Dandolo, was in his nineties and blind, but his mind remained razor-sharp. He had no intention of letting his shipyards sit idle or his investment vanish. Instead of releasing the crusaders from their debt, he proposed a diversion. The Dalmatian city of Zara, a Christian rival of Venice that had recently thrown off Venetian rule, lay conveniently on the route east. If the crusaders would help recapture it, the Doge would defer the balance. The papal legate threatened excommunication, but the crusade leaders, desperate and indebted, accepted. In November 1202, Zara fell after a brief siege. Its walls were razed, its wealth plundered. Pope Innocent III duly excommunicated the entire expedition — then quietly lifted the ban on the crusaders, leaving only the Venetians under interdict, because he needed the army to reach the Holy Land.

The Prince and the Promise

Winter quarters in Zara brought an unexpected visitor. Alexios Angelos, son of the deposed Byzantine emperor Isaac II, had escaped from prison and fled to the West. He offered the crusaders a staggering deal: if they would sail to Constantinople and restore his father to the throne, he would pay the entire Venetian debt, contribute 200,000 marks to the crusade, provide 10,000 Byzantine soldiers for the Egyptian campaign, and place the Eastern Church under papal obedience. For the Venetian Doge, the offer was irresistible. It promised not only repayment but the strategic dominance of the eastern Mediterranean that Venice had coveted since the days of the Fourth Crusade's planning. For the crusade leaders, it was a lifeline. They agreed.

The fleet reached the walls of Constantinople in June 1203. The city, the greatest metropolis of Christendom, had stood unbreached for nearly nine centuries. Its triple land walls, built by Theodosius II, were a marvel of military engineering. Its sea walls, guarded by the great chain across the Golden Horn, had turned back Arab fleets and Rus raiders alike. Inside, the population of perhaps 400,000 lived amid churches, palaces, and forums that held the accumulated art and learning of the Roman world. The crusaders were awestruck. "One would not believe there could be so rich a city in all the world," wrote Geoffrey of Villehardouin, the expedition's chronicler.

The First Siege

The initial assault targeted the sea walls along the Golden Horn. Venetian galleys, their bows fitted with flying bridges, crashed against the defenses while knights stormed ashore. The Byzantine garrison, demoralized and poorly led, broke. The usurper Alexios III fled the city in the night, taking a fortune in treasure. Isaac II was restored, and his son Alexios IV was crowned co-emperor. The new regime immediately confirmed the crusaders' demands. But the imperial treasury was empty. The promised 200,000 marks did not exist. Alexios IV ordered the melting down of church plate and icons to raise funds, sparking outrage among the populace. Tensions mounted through the winter. In January 1204, a popular uprising brought a new emperor, Alexios V Doukas — "Mourtzouphlos" — to power. He promptly executed Alexios IV and repudiated the treaty.

The crusaders, now stranded before a hostile city with no money, no supplies, and no prospect of reaching Egypt before the campaigning season ended, faced a choice: retreat in disgrace or take the city by force. They chose the latter. On April 9, 1204, they launched a general assault. The Byzantines repelled it. Three days later, they tried again. This time, a favorable wind drove the Venetian ships hard against the sea walls. Knights poured across the flying bridges. A small force, led by a French knight named André d'Urre, forced a postern gate. The defense collapsed. By nightfall on April 12, the crusaders held the city.

Three Days of Fire

What followed was not a military occupation but an orgy of destruction. For three days, the army that had taken the cross to fight for Christ's tomb turned on the most Christian city on earth. They killed civilians indiscriminately. They raped nuns in the convents. They smashed icons, tore gold leaf from mosaics, and melted down priceless reliquaries for their bullion. The great bronze horses of the Hippodrome were shipped to Venice, where they still stand on the façade of St Mark's Basilica. The Library of Constantinople, repository of countless ancient texts, was burned. A prostitute was enthroned in the patriarch's chair in Hagia Sophia and sang bawdy songs while soldiers drank communion wine from the chalices. "Never since the beginning of the world had so much booty been won in a city," Villehardouin wrote, "for if they had not taken it, the wealth of the world would have been less by half."

The Doge Dandolo, blind and ancient, took the title "Lord of a Quarter and Half a Quarter of the Roman Empire." Venice claimed the choicest ports and islands — Crete, Euboea, the Cyclades, the strategic harbors of Modon and Coron. The rest was divided among the crusader barons: the Kingdom of Thessalonica, the Principality of Achaea, the Duchy of Athens. The Latin Empire of Constantinople was established, with Baldwin of Flanders as emperor. But it was a phantom realm, controlling little beyond the city walls.

The Long Shadow

The Fourth Crusade never reached the Holy Land. The knights who had sworn to liberate Jerusalem instead carved out feudal fiefs on the ruins of the Eastern Roman Empire. The Byzantine state fragmented into three successor states — Nicaea, Trebizond, and Epirus — each claiming the imperial title. Though the Empire of Nicaea would recapture Constantinople in 1261, the restored Byzantium was a shadow of its former self, stripped of its wealth, its territories, and its strategic depth. The great chain across the Golden Horn was never the same barrier again. The Venetian quarter in the city became a state within a state.

The theological rupture was equally profound. The schism of 1054 had been a dispute between patriarchs and popes; the sack of 1204 made it a wound in the body of the faithful. Orthodox chroniclers recorded the desecration of Hagia Sophia as a trauma that no diplomacy could heal. When the Ottoman Turks finally breached the land walls in 1453, they found a city already hollowed out, its population a fraction of its medieval peak, its empire reduced to a handful of Aegean islands and a strip of Thrace. The Latin conquest of 1204 had done what centuries of Muslim sieges could not: it broke the spine of the Eastern Roman Empire.

In the end, the only lasting victor was Venice. The Republic's stranglehold on the eastern trade routes, secured by the ports and privileges seized in 1204, funded its Renaissance grandeur and sustained its power for another three centuries. The Doge's gamble had paid off beyond imagining. The crusaders' debt was paid in the blood and treasure of their fellow Christians, and the road to Jerusalem remained closed.

This is one episode in a much longer story. For the full account of the Fourth Crusade and the sack of Constantinople, read “A History of the Mediterranean” by Franco Aquilina on MixCache.com.