After three long years, the campaign reached its climax. In June 1099, a crusader army arrived outside Jerusalem and stared up at its towering walls. From late 1095, men, women and children from western Europe had left their homes and set out east on a vast military expedition that would take them to the Holy Land. Now, after enduring lightning ambushes, desperate sieges and periods of near starvation, the jewel in the crown of Christendom was in their sights.
But not yet within their grasp. Between the crusaders and the conquest of Jerusalem stood the city's determined defenders. These troops of the Fatimid caliphate – a Shia Muslim empire spanning north Africa and parts of the near east, with its capital in Cairo – guarded a population of perhaps 20,000 Muslims, Jews and eastern Orthodox Christians massed within.
At first, the defenders prevailed, resisting everything the increasingly frustrated crusader forces could throw at them. But then, after weeks of skirmishes and as a last resort, the nobleman Godfrey of Bouillon used a siege tower to gain a priceless toehold on the walls to the north of the city, and was able to open the nearest gate.
