I‘ve been thinking a lot recently about several issues around the Kommenian restoration and the international politcal scene prior to the 4th crusade, particularly around Byzantine-Venetian relations. The standard histories detail the 1054 schism, some problems during the Crusades and relative peace until the 1204 Siege of Constantinople. If anything, there was a series of low level conflicts and tension during the majority of the previous century.
A Bad Marriage
In the late 11th century, the Normans took the remainder of Byzantine possessions in Italy and Sicily and were threatening Byzantine possessions in the Balkans. In a desperate act to gain naval support, Alexios Komnenos granted special trade rights to the Venetians through the Chrysobull of 1082. They were granted Byzantine tax exemptions and received their own special trading district in the capital. In exchange, the Venetians were to provide naval intervention on behalf of the Byzantine state.
Arguably one of the worst deals in history, this had profound consequences for Venice as it kicked their economic and state development into high gear. Over the next 100 years Venetian trading power eventually choked off competition of Byzantine merchants. Venice really had no love for Byzantium or motivation to protect them beyond their new source of income.
This situation created an interesting paradox of Byzantine leaders unable to undo or reduce these privileges. They lacked the naval forces to change the balance of power so continued to depend on an unreliable Venice for this support. Byzantium really needed the support of Venice in her conflicts against her enemies, but this relationship was toxic to the empire. Common sense dictates a large revenue source diverted to a foreign nation for protection undermines their own national security.
Untying the Knot
As a result, Byzantine leaders were motivated to undo the agreement. Upon the ascension of John Komnenos, he refused to confirm the Chrysobull of 1082 and remove their special tax free status. Soon after, the Venetians attacked Corfu on their way to Crusade. In retaliation, John exiled the Venetians in the capital which only escalated the conflict. Doge Domenico Michele leveled the city of Methoni and pillaging continued until 1126. John Komnenos finally confirmed and extended their trading privileges. Doge Michele’s tomb reads the “Greek Terror, Praise of the Venetians.”
As an effort to undermine Venice’s position in the capital, Manuel Komnenos cultivated relationships with her rivals Genoa and Pisa. Similar agreements were created, in the thought that they could get similar protections without the attitude.
Once Manuel felt comfortable with cutting ties with Venice, he imprisoned some 10,000 Venetians in Constantinople in 1171. Public opinion turned decisively against the Byzantines in Venice and the people clamored for war. After several rather indecisive battles, plague set in the Venetian camp while waiting for negotiations. Manuel stalled in negotiations while letting the plague set in with the Venetian navy. As time passed, the Venice’s navy was decisively destroyed.
Of course, things came to a head in 1182 with the Massacre of the Latins. Tens of thousands of westerners were massacred in the capital and Cardinal John was beheaded.
The Massacre of the Latins event has been pointed to as a sort of casus belli for the Venetians attack in the 4th crusade. Obscured by modern nationalist rhetoric, Enrico Dandolo never took it personally and was back to the previous status quo settling several new trading agreements shortly thereafter.