The Sack of Constantinople in 1204 was a plot twist no Westerner or Byzantine could have predicted. After four crusades and decades of cooperation between the Latin Church and the Byzantine Emperors, the crusaders turned on Constantinople.
They not only rampaged the city, looting and destroying its treasures, but they raped its women and subsequently divided the conquered lands between themselves. But you may remember that the goal of the crusaders had always been to recapture the Holy Land of Jerusalem. What could have led to this seemingly noble aim descending into greed and anarchy?
Constantinople
The ancient city of Constantinople is known today as Istanbul, located in modern-day Turkey. Its location between Asia and Europe and its natural harbour meant that geographically it had many advantages; Constantinople's trading port thrived because of this. Founded in 330 AD, this successful and powerful city was once the capital of the Roman Empire, the Latin Empire, and the Ottoman Empire!
Fig. 1 - Constantinople in Byzantine times
Did you know? Constantinople was created by and named after Constantine the Great, the first Roman Emperor to convert to Christianity!
Siege of Constantinople
The Fourth Crusade (1202-1204) was just one in a series of religious campaigns to recapture Jerusalem.
Nonetheless, the many years of fighting since the First Crusade in 1095 had led to economic issues all around Europe. The monarchs of Europe refused to engage in another crusade due to their depleted finances. As a result, an Italian aristocrat named Marquis Boniface of Montferrat took over the leadership of the crusade.
Did you know? Pope Innocent III encouraged the Fourth Crusade in 1202!
Who was involved in the Fourth Crusade (1202-1204)?
The belligerents of the Fourth Crusade included groups from:
- The Kingdom of France.
- The Holy Roman Empire.
- The Republic of Venice.
- Byzantine Empire.
- Kingdom of Hungary.
- Kingdom of Croatia.
- Ayyubid Sultanate.
Despite the financial strain of the Crusades, the Kingdom of Venice demanded the 240 ships they had afforded for the crusade to be paid with 85,000 silver marks. This sum was double the amount of France's yearly income at the time! The demand spelt out the fragile European economy that drove the crusaders to view the crusades as a way to gain money rather than recapture a centre of spiritual importance.
Belligerent
A nation recognised to be engaged in a conflict by international law.
Fig. 2 - Venetian ships attacking Constantinople
Unable to pay such a hefty price, the crusaders made a deal with the Venetians. The crusaders would attack Zara with the 50 warships provided by the Venetians in return for half of the territory claimed during the crusade. Once news got out of the sack of Zara, the Pope excommunicated the Venetians and Crusaders as Zara was a Christian City. This ex-communication lasted only briefly, as the Pope needed these groups to strengthen his crusade.
Sack of Constantinople Timeline
The conflict and betrayal that stretched across two years (1202-1204) saw many casualties, crimes and crucial changes for the Byzantine Empire. The table below highlights the most important key dates to know during this period of conflict!
| Date | Event |
| 1202 CE | The Fourth Crusade was formed. |
| 24 June 1203 | Crusaders arrived and attacked Constantinople. |
| January 1204 | Alexios IV and Isaac II were executed. |
| 8 - 13 April 1204 | The looting of Constantinople took place. |
| 14 April 1204 | The army of the Fourth Crusaders sacked Constantinople. |
| 9 May 1204 | The first Latin Emperor of Constantinople was named: Count Baldwin of Flanders. |
| 1261 | The Byzantine Empire was re-established. |
Conquest of Constantinople
A essential factor in the eventual siege and fall of Constantinople was the distrusting relations between the Christians of the East and the West. The Byzantines never fully accepted the concept of a Holy War, which they saw as degrading to the noble nature of Christianity. They essentially viewed the Western crusaders as an unruly mob of looters and rapists (acts which, to the embarrassment of the Western Church, they did engage in).
On the other hand, the West believed that the Byzantine Emperors were indifferent to the Crusades and merely wanted to preserve their Empire and the status of Constantinople as the largest and most glorious Christian city. The mistrust carried well into the 13th century and played a crucial role in the decision of the Western crusaders to attack Constantinople.
Fig. 3 The Byzantine Empire Map 1020
The objective of the crusaders had been Jerusalem from the start. So what changed?
Doge Enrico's previous expulsion from Constantinople while acting as Venetian ambassador left a residue of bitterness. And so, in his determination to secure domination of trade for the Venetians throughout the East, his actions were less than noble. Doge Enrico formed a secret deal with Alexios IV Angelos, who had been deposed in 1195.
Alexios IV Angelos
Son of Isaac II Angelos and Western sympathiser.
Enrico believed that by placing Alexios on the Byzantine Empire's throne, the Venetians would have access to better trading opportunities than their enemies: Pisa and Genoa. Some crusaders favoured the security of Papal supremacy that this would give over the Eastern church. In contrast, others were interested in the wealth of Constantinople. The consequences of these plans meant that the crusaders could seize Jerusalem with increased financial capacity.
Fall of Constantinople
On 24 June 1203, the crusaders arrived at Constantinople, bringing an impressive force of around 30,000 Venetians, over 14,000 infantrymen and a total of 4,500 knights! With this large force, they attacked Byzantine garrisons near Galata, catching Emperor Alexios III Angelos by surprise and resulting in his fleeing from the city.
Incumbent
A person who currently holds a post or position in office.
Having secured the people's and the army's support, Alexios V Doukas, a commander and senior diplomat, usurped the throne from the incumbent Emperor Alexios III Angelos by staging a palace coup. To kill his predecessors, Alexios V Doukas had Alexios IV and Isaac II executed in January 1204. Alexios V promised to defend the city. He strengthened the Theodosian Walls and initiated raids on crusader camps to weaken them. These military efforts made him popular, yet later proved ineffective against the crusaders.
Fig. 4 The Byzantine Emperor Alexios V Doukas
Did you know? Alexios V Doukas claimed to be the son of Isaac Coukas Mourtzouphlos. But some historians debate whether he was in the female line for the crown, as the great-great-grandson of Emperor Alexios I Komnenos.
Battle of Constantinople
The crusaders overwhelmed the walls of the city. Once they had overcome the Byzantine garrison at Galata, they could lower the chain blocking access to the harbour at Golden Horn. After this, the crusaders steered their fleet toward the sea and land defences of the city simultaneously. The attack was so overwhelming that even the Varangian Guard could not prevent the fall of Constantinople.
The Varangian Guard
The Varangian Guard was a specialised unit of primarily mercenary soldiers acting from the 10th to the 14th century. They were specially trained to act as defenders of the Emperor. A deliberate policy meant they were mostly sourced from Scandinavia and Anglo-Saxon regions. This was to prevent them from having political leanings which might influence their loyalties to the ruling Byzantine Emperor.
The Looting of Constantinople
Constantinople, a rich city at the time, was utterly destroyed by the looting crusaders between 8-13 April 1204. Several valuable sculptures, artworks, and jewels were destroyed, seized, and melted down for coinage.
Fig. 5 Saint Peter and Saint Paul with shroud
One of the most valuable Byzantine treasures said to be seized was the Mandylion shroud, a scarf said to have had an impression of Christ. It is believed that it was taken as a prize to France but was destroyed during the French Revolution, which began in 1789. The Crusaders also seized a gold reliquary containing a frame of the True Cross, which was placed in the Cathedral of Limburg in Germany.
Reliquary
A storage item where sacred relics may be contained.
The Hippodrome of Constantinople, where chariot races took place, was also looted. For example, the four bronze horses, which are now part of St Mark's Cathedral in Venice, originally belonged to the arena's entrance gate. The destruction left a mortal mark on the city and the Christian world, as Christians had attacked other Christians. Historian J.J. Norwich has remarked that:
By the sack of Constantinople, Western civilization suffered a loss greater than the burning of the library of Alexandria in the fourth century or the sack of Rome in the fifth - perhaps the most catastrophic single loss in all history.1
Consequences of the Sack of Constantinople
Following the Sack of Constantinople, the Byzantine Empire was weakened and distributed among Venice and its allies. The table below outlines the resulting gains of this agreement that followed the instructions of the 1204 Partitio Romaniae treaty.
| Venetians | Boniface |
| Three-eighths of Constantinople. | Thessalonica. |
| The Ionian Islands | Formed a new kingdom which included Athens and Macedonia. |
| Several Greek islands in the Aegean. | |
Count Baldwin of Flanders was crowned on 9 May 1204 as the first Latin Emperor of Constantinople. Many Byzantines refused to recognise Flanders as their leader, and the empire was fragmented into four separate conflicting states. The Byzantine Empire would not be re-established until 1261, under Emperor Michael VIII.
Sack of Constantinople - Key takeaways
- The Sack of Constantinople took place between the 8-13 April 1204.
- The main causes of the siege of Constantinople were the financial issues created due to the previous crusades and the mutual distrust between the East and West.
- The crusaders plotted with the deposed Alexios IV and his father, Isaac I. However, their plans were frustrated as they were very unpopular in Constantinople.
- The crusaders looted precious treasures from the city, such as the Mandylion shroud and the four bronze horses of the Hippodrome.
- The Venetians took three-eights of Constantinople, the Ionian islands and several Greek islands in the Aegean after this conflict under the Partitio Romaniae Treaty.
References
- J.J. Norwich, A Short History of Byzantium by John Julius Norwich, 2017, pp. 306.
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