In June of 1099 [the First Crusade] arrived before the walls of Jerusalem, which was then held by the Fatimid Arabs of Egypt. With their usual religious zeal and grim determination, the Christians prepared to attack the walls.
Their fighting force had been reduced to 1,200 knights and 10,000 foot soldiers, with a similar number of noncombatants who proved to be quite useful in carrying water, wood, and other supplies. A small fleet of Genoese ships arrived at a nearby port with more supplies and wood for the building of siege engines. An Egyptian fleet followed behind and destroyed the vessels, but fortunately the sailors, all trained workmen, salvaged the woodworking tools. They built three huge wooden towers, the third story of which consisted of a drawbridge that would provide an avenue of attack when lowered on to the ramparts.
In spiritual preparation for the attack, the Christians marched barefooted in solemn procession around the wall over to the Garden of Olives. From the height of the ramparts, the Moslems ridiculed the piety of the warriors and blasphemed Our Lord. From below the Crusaders vowed to avenge the honor of Jesus Christ. On the last day of the assault, Godfrey climbed one of the towers. The drawbridge came flying down onto the north wall. He and Eustace, his brother, led the Rhinelanders and Tancred’s Normans against the defenders on the wall and down into the city. The remaining Crusaders broke into the city at other points. They overcame a spirited resistance that ended in a general massacre.
Jeremias Wells, History of Western Civilization (n.p., n.d), pp. 236-237.
Video: The Walls of Jerusalem