After the fall of Jerusalem, there was no one left save the conquerors. The massacre had taken the lives of all the Jews, many having been burned in the synagogue where they had taken refuge. All the Moslems were dead. Any Christian pilgrims had been expelled before the siege had begun. The Moslems would never forget or forgive the behavior of the Crusaders. Jerusalem was a Holy City to them as much as it was to the Christians. With sacred shrines looted and innocent people slaughtered, it only confirmed their belief that all Westerners were savage barbarians.
Soon after the Crusaders had taken Jerusalem, a great army of Moslems swept up from Egypt to encamp Ashkelon on the Palestinian coast west of the holy city. Despite being heavily outnumbered by the Christians, lead by Godfrey of Bouillon, Tancred of Taranto and Robert of Normandy, the Christians took the offensive and road out of Jerusalem towards the enemy.
At dawn the knights made a sudden charge into the center of the Moslems camp and took them completely by surprise. In the battle that followed, the entire Egyptian army was shattered with a few survivors taking refuge in the fortress of Ashkelon. When the garrison refused to surrender them, the victorious Crusaders returned to Jerusalem, satisfied they had eliminated any threat to their rule.
This battle ended the offensive phase of the first crusade, with five small Christian states being set up in Antioch, Edessa, Tripoli, Jerusalem and Galilee.