Proving Josephus: Research on Roman Ballistics Confirms Second Temple Battle Account

For the first time in the research of ancient Jerusalem, physical evidence uncovered in recent excavations has proven Jewish historian Josephus Flavius’s account of the 70 CE conquest of the holy city.

Through computer analysis of 2,000-year-old Roman ballistics uncovered in Israel Antiquities Authority excavations in Jerusalem’s Russian Compound near modern Jerusalem’s Municipality building, archaeologist Kfir Arbiv claims he has demonstrated the veracity of Josephus’s narrative charted in his book, “The History of the Jewish War against the Romans.”

“It is extremely exciting to be proving the narrative of Josephus onsite,” Arbiv told The Times of Israel on Sunday, Tisha B’av, the Jewish day of mourning that annually commemorates the conquests of Jerusalem.

All data gathered onsite was compared to Josephus’s contemporary descriptions of a battle near the city’s third line of defense — which were proven accurate, said Arbiv. This is significant because while Josephus’s histories are one of the sole contemporary sources of the fall of Jerusalem, they are treated carefully by scholars due to his colorful personal history.

Born Joseph Ben Matthias to a priestly family circa 38 CE, Josephus was a leading Jewish military leader during the Jewish revolt until he was captured by the Romans in 67 CE. Taken in chains to Rome, Josephus eventually won his freedom through a “prophecy” that Vespasian would become emperor. Newly loyal to Rome, Josephus returned to Jerusalem with Vespasian’s son Titus for the conquest in 70 CE, ostensibly to act as a mediator. Reviled by both sides, Josephus failed to quell the flames of war and eventually returned to Rome where he composed his histories.

“With the help of the computer, I located all the ballista exactly where they were found. I took into account the local topography and the location of the Second Temple-period city fortification walls, and I made ballistic calculations, including the launching angle, and the throwing distance of the stones,” said Arbiv, who co-directed the excavations with the IAA’s Dr. Rina Avner. The research is part of Arbiv’s Tel Aviv University MA thesis.

According to the IAA, the Roman Arsenal exposed in the Russian Compound excavations so far includes hundreds of ballista stones. The sizes vary and some were launched from hi-tech bolt-throwing machines to a distance of 100–400 meters, whereas other small sling stones were used by infantry. Ancient arrowheads, projectile spears and swords were also discovered onsite.

By taking measurements of the absolute height of the in situ ballistics and the use of a computer algorithm, Arbiv said he was able to prove that the radius of the fallen stones’ launches corresponded to Josephus’s described 300-400 meters.

“It’s very exciting to read the history and then see it playing out in front of your face,” Arbiv told The Times of Israel. “To pick up a rock from 2,000 years ago that a Roman solder once held and now you’re holding it in your hand? It’s amazing.”

The IAA’s Russian Compound excavations have previously exposed part of the Third Wall, the third line of fortifications that surrounded outer Jerusalem.

This new research is, in part, aimed at proving the probable spots in which the Roman army first penetrated the city. Future efforts will likely turn to this topic, said Arbiv.

There are already indications of unusual activity found in the Russian Compound dig. Near a location nicknamed “Cat’s Square,” the excavators discovered a large concentration of ballista stones, including some broken after use. According to Arbiv, the Roman army evidently viewed it as a strategic point and upwards of a thousand ballista stones were launched here.

“This is not surprising, as whoever controls this spot dominates the whole area and the fate of the city. This aligns with Josephus’ account that Titus commanded to penetrate the city from the northwestern side of the city wall,” Arbiv said in an IAA press release.

“The Temple was destroyed in 70 CE, after a four-month siege and an intensive battle led by the Roman general Titus in order to conquer the city and suppress the revolt initiated by the Jews four years earlier. The Romans had a well-trained massive army, equipped with the best military innovations of their day. It was a ruthless war machine.”

In conversation Sunday, Arbiv described his ballistics research as bringing the Roman soldiers’ battlefields to life.

“In the over 150 years that we are scientifically researching ancient Jerusalem, this is the first time that we’ve resurrected a battlefield that proves an account of the conquest of Jerusalem,” he said.

“It is the clearest and most beautiful connection to the historical events that we have to date,” said Arbiv.

Reporting from The Times of Israel.