The First Crusade Army That Took Jerusalem on 15 July 1099 and Killed Most of the City's Population in Two Days

The First Crusade had been preached by Pope Urban II at the Council of Clermont on 27 November 1095. The stated objective was the recovery of Jerusalem from Seljuk Turkish control. The Crusade’s military force — approximately 60,000-100,000 combatants and non-combatants at peak strength — had marched from western Europe across the Byzantine empire and the Islamic Near East from 1096 to 1099.

The army that reached Jerusalem on 7 June 1099 had been reduced by attrition to approximately 12,000-15,000 effective soldiers. The siege was complicated by the city’s defensive geography (Jerusalem sits on a elevated rock plateau with steep approaches), by the absence of nearby fresh water, by the Crusaders’ lack of siege engines, and by the midsummer Levantine heat.

The siege

The Fatimid garrison commander Iftikhar al-Dawla had approximately 1,000 troops — Egyptian Sudanese infantry, Armenian mercenary archers, and Fatimid officers. The civilian population was approximately 20,000-30,000, predominantly Muslim and Jewish, with a smaller Christian minority. Iftikhar had ordered the expulsion of the Christian population shortly before the Crusader arrival to prevent fifth-column action; many of the expelled Christians joined the Crusader camp.

The initial Crusader assault on 13 June 1099 failed for lack of siege equipment. The Crusader leadership — particularly Godfrey of Bouillon, the Lorraine duke commanding the northern army, and Raymond IV of Toulouse, commanding the southern army — spent the next month building siege towers from timber stripped from Genoese ships that had reached Jaffa with reinforcements.

The second assault began on 13 July 1099. By the evening of 14 July a Crusader tower had been brought up against the northern wall under Godfrey’s personal command. The wall section was breached early on the morning of 15 July 1099. The Crusader army poured into the city through the breach.

The massacre

The events of 15-16 July 1099 inside Jerusalem are recorded in multiple contemporary sources — the anonymous Latin Gesta Francorum, the chronicles of Raymond of Aguilers and Fulcher of Chartres on the Crusader side, the later Arabic chronicles of Ibn al-Athir and Ibn al-Qalanisi on the Muslim side. The sources agree on the basic facts and agree on the scale.

The Crusader army conducted a systematic massacre of the city’s population for approximately 36 hours. The estimated death toll is between 10,000 and 30,000 — the higher figure from Ibn al-Athir, the lower from the more restrained Latin accounts. The dead included combatants and civilians, men, women, and children. The Muslim population took refuge in the Al-Aqsa Mosque on the Temple Mount; the Crusaders broke in and killed everyone inside. The Jewish population took refuge in the central synagogue; the Crusaders set fire to the building with the population inside.

Raymond of Aguilers, an eyewitness, wrote in his contemporary chronicle:

In this temple [of Solomon] about 10,000 were beheaded. If you had been there, your feet would have been stained up to the ankles with the blood of the slain. What more shall I say? Not one of them was allowed to live. Neither did they spare the women nor the little children.

The Latin sources treated the massacre with religious satisfaction. The Arabic sources treated it as a foundational atrocity. The Islamic religious-political memory of the First Crusade has, since the late 11th century, been organised around the specific event of 15-16 July 1099.

The Latin Kingdom

The Crusader leadership elected Godfrey of Bouillon as the head of the new political order on 22 July 1099. He refused the title of “King of Jerusalem” on religious grounds — that he could not wear a golden crown in the city where Christ had worn a crown of thorns — and accepted instead the title Advocatus Sancti Sepulchri (“Defender of the Holy Sepulchre”).

Godfrey died of plague at Jerusalem on 18 July 1100 — approximately a year and three days after the city’s capture. His brother Baldwin took the royal title without the religious scruples and was crowned Baldwin I of Jerusalem at Bethlehem on Christmas Day 1100. The Kingdom of Jerusalem existed as a distinct political entity from 1099 to 1291, with the Latin-controlled territory shrinking progressively from approximately 1180 onwards.

The city of Jerusalem was lost back to Saladin on 2 October 1187, after the Crusader defeat at the Battle of Hattin three months earlier. Saladin’s reconquest was less violent than the 1099 Crusader capture had been — most of the Latin population was permitted to leave with their property in exchange for ransom payments. The 1187 reconquest re-established Muslim control of the city for the next 730 years (until British capture in December 1917).

The Al-Aqsa Mosque was reopened for Muslim worship in October 1187. It is still operating in 2026. The direct material continuity of the building between the 11th century and the present is unusual for a contested religious site of comparable historical importance.