Recent excavations south of Jerusalem unearthed a ditch used to defend against siege towers, along with a ruined house Crusaders may have used as cover during a battle. The finds confirm some oft-questioned details of historical accounts of the First Crusade, including how a ditch along the city’s southern wall thwarted the attacking siege engines. And this new evidence provides tangible links to events recorded 920 years ago.

The end of a five-week siege

In July 1099, European armies, fresh from the siege of Antioch, converged on Jerusalem (then ruled by the Muslim Fatimid Dynasty) and attacked the walled city from two sides. On the north, the crusaders would eventually breach the walls and perpetrate a slaughter that still echoes across the centuries. But on the south, a deep, wide ditch just outside the city’s wall kept the siege towers from closing to disgorge their cargoes of armed men.

A priest traveling with the army of Raymond de Saint Gilles, the Count of Toulouse, described the ditch and the crusaders’ efforts to advance. Toulouse reportedly offered his troops an extra payment of gold dinars to venture close to the guarded walls under cover of darkness and fill in part of the ditch. The Frenchmen succeeded; their siege tower got through, slamming against the stone wall of Jerusalem to bring them face to face with an enemy who had traded arrow volleys with them for the last five weeks.

Despite that small victory, the southern assault on Jerusalem failed. Even with a few siege towers in place, the southern wall was too well-defended to breach. Although Jerusalem’s southern defenses held, the invaders ultimately overran the city. And when they did, there was nothing noble or holy in their conquest.

“The chroniclers talk about ‘rivers of blood’ running in the streets of the city, and it may not be an exaggeration,” said project co-director Shimon Gibson, a historian at the University of North Carolina at Charlotte, in a recent statement. Amid looting, burning, and worse, crusaders slaughtered Muslims, Jews, and even local Christians, whom they considered heretics. “They turned Jerusalem into a ghost town,” said Gibson.

Historians mostly agree that medieval observers’ accounts of the bloody sacking of Jerusalem and blood on the streets in the summer heat were accurate. But they’re more skeptical about Toulouse and others’ descriptions of the siege itself, especially the part about the ditch and the siege towers. After all, there was no sign of a trench anywhere near the southern wall. “The ditch got filled in and it disappeared—to such an extent that a lot of archaeologists who had been working at different points in time believed that maybe this ditch was a figment of the chroniclers’ imaginations,” said Gibson.

Long-buried earthworks

Gibson and his colleagues unearthed the trench, filled with soil and debris and buried beneath layers of later sediment, during a recent excavation on the slopes of Mt. Zion, just outside the wall that now stands where the Fatimid wall stood 920 years ago.

In earlier seasons of fieldwork at the site, archaeologists had noticed something odd about the ground near the wall. For the most part, the hillside of Mt. Zion slopes downward from the southern wall of the city, but one layer of soil sloped upward. “That was our first clue,” said Gibson. “There was some feature that had been cut into the ground, which had been filled in later.” This season, they carefully excavated the filled-in outlines of a 4m (13 ft) deep trench cut into the hillside, creating a 17m (56 feet) wide obstacle at the base of the southern wall. The firmer, undisturbed soil of the trench walls was relatively easy to tell apart from the looser, disturbed soil that had filled in the trench later.

Among that loose fill, archaeologists found fragments of pottery and a scrap of metal that may have come from a crusader's battle standard. They also identified several broken pieces of a type of green-glazed ceramic called celadon ware, produced in China since around 200 BCE. That suggests that either shortly before or shortly after the Crusade, trade networks connected Jerusalem with distant China.

A layer of ash and charred sediment just above the filled-in ditch helped date it to around 54 years after the time of the First Crusade. Around that time, the fifth crusader King (the fourth if you exclude Godfrey of Bouillon, who refused to call himself a king but pretty much functioned as one), Baldwin III, burned large portions of Jerusalem. That was the result of a civil war with his mother, Queen Melisende, who had been reluctant to relinquish the reins of power once her son came of age.

Scattered among the burned layer above the ditch, archaeologists found coins dating from the reign of Baldwin III. The remains of the fire, backed up by the dates on the coins, suggest that the ditch must have been dug into the slopes of Mt. Zion and filled in again sometime before Baldwin III’s destructive family dispute. That’s a good match for the timing of the First Crusade.

“The remains of the frontline battle”

Not far outside the wall, Gibson and his colleagues found the buried ruins of a building they say was probably already a crumbling ruin when the crusader forces happened upon it. It was once one of a scattered group of buildings outside the city’s walls, and it appears to have suffered damage during an earthquake in 1033. But apparently enough of the structure remained standing to offer a little shelter from the Fatimid defenders’ arrows. On the building’s floor, 920 years later, lay arrowheads and a few of the bronze cross pendants usually carried by crusaders.

Something else stood out amid the martial artifacts left behind on the floor of the ruined house: an ornate golden headpiece the crusaders had probably looted along the way. The piece is an ornate construction of gold and pearls, crafted in a style popular in 11th-century Egypt (the capital of the Fatimid Dynasty was in Cairo).

It’s a large and fantastically expensive piece of jewelry—not the sort of thing you lose behind the couch or under the bed—so Gibson and his colleagues don’t think it belonged to anyone who once lived in the house. There’s no way to prove for sure what happened, but stacks of historical accounts describe the crusaders looting the cities they conquered. The headpiece may well have been the spoils of war, perhaps carried by an opportunistic soldier from the army’s previous victories at Nicea or Antioch.

The artifacts hint at a narrow but vivid slice of the battle: a group of crusader soldiers, perhaps some of Toulouse’s men, hunkered down among the ruins of a Muslim house while arrows arced down from the city’s walls to clatter on the floor around them. We’ll never know if they died there, or in the taking of the city, or if they lived to take part in the brutality of its sacking.

“Not only do we have the remains of the ditch that we only knew about from the sources, but we also have the remains of the frontline battle itself,” said project co-director Rafi Lewis of the University of Haifa in a recent statement. Future excavations may find more artifacts and earthworks to help archaeologists and historians reconstruct the course of the battle—from the major flow of events like the failure of the southern assault to smaller eddies in the course of history, like the soldiers taking shelter in the ruined house.