Zara: The Unholy Holy Crusaders

The Assault on the City of Zara

Venice had been deprived of the city of Zara by the Hungarians who had conquered it. Not only was this a loss in itself, but it also was a potential rival to their ambition of dominating the trade of the Mediterranean. And yet, Venice didn't possess the army it required to re-conquer this city.
Now however, with the massive crusading army indebted to it, Venice suddenly had found such a force.
And so the crusaders were presented with the Doge's plan, that they should be carried to Zara by the Venetian fleet, which they should conquer for Venice. Any spoils thereafter would be shared between the crusaders and teh Venetian republic.
The crusaders had little choice. For one they owed money and saw any loot they should capture in Zara as the only means of repaying their debt. On the other hand they well know that, if they should not agree with the Doge's plan, then supplies such as food and water would suddenly fail to arrive which which to feed their army on their little island off Venice.
Zara was a Christian city in the hands of the Christian King of Hungary. How could the Holy Crusade be turned against it ?
But want it or not, the crusaders had to agree. They had no choice.
Papal protestations were made; any man to attack Zara would be excommunicated. But nothing could stop the impossible from happening, as the Crusade as hi-jacked by Venice.
In October 1202 480 ships left Venice carrying the crusaders to the city of Zara. With some stops in between it arrived on 11 November 1202.
The city of Zara stood no chance. It fell on 24 November after five days of fighting. Thereafter it was thoroughly sacked. In an unimaginable twist of history the Christian crusaders were ransacking Christian churches, stealing everything of value.
Pope Innocent III was furious, and excommunicated every man who had taken part in the atrocity.
The army now passed the winter in Zara.
Message was sent by the crusaders to pope Innocent III, explaining how their dilemma had forced them to act in service of the Venetians. In consequence the pope, hoping that the Crusade might now resume its original plan of attacking the forces of Islam in the east, agreed to restore them to the Christian church and hence annulled his recent excommunication.

http://www.roman-empire.net/constant/1203-1204.html

Further readings:

http://www.britannica.com/EBchecked/topic/655932/Siege-of-Zara
http://en.wikipedia.org/wiki/Fourth_Crusade#Attack_on_Zara
http://www.spiritus-temporis.com/fourth-crusade/attack-on-zara.html