The original intention of the Fourth Crusade was to reconquer Jerusalem, lost by the crusaders to Saladin’s forces in 1187. Swayed by the Venetian government, to whom they owed a great deal of money, the Crusaders abandoned their earlier plan of attacking Cairo (seat of the Ayyubid Sultanate, who ruled Palestine) to instead attack for Zara (a rebellious province of Venice) and then Constantinople (the greatest political and mercantile opponent of Venice).
The siege of the city began on June 23, 1203, with the crusaders’ arrival at Constantinople. The crusading forces numbered a little over 20,000 (including the sailors and marines of their fleet), as compaed to the city’s standing garrison of 15,000, which defended a population of approximately 500,000 people. Both sides settled in to wait out the other, but in the end, it was the invaders who triumphed, proceeding to sack the city for three days after their victory, and looting it of an estimated 900,000 silver marks. In the aftermath, the Byzantine Empire was divided into smaller states, many of them clients of the armies who had invaded it.
