sieges, for example, formed the core of Julius Caesar's mid-1st-century BC conquest of Gaul (modern France). In his Commentarii de Bello Gallico (Commentaries on the Gallic War), Caesar describes how, at the Battle of Alesia, the Roman legions created two huge fortified walls around the city. The inner circumvallation, , held in Vercingetorix's forces, while the outer contravallation kept relief from reaching them. The Romans held the ground in between the two walls. The besieged Gauls, facing starvation, eventually surrendered after their relief force met defeat against Caesar's auxiliary cavalry. The Sicarii Zealots who defended Masada in AD 73 were defeated by the Roman legions, who built a ramp 100 m high up to the fortress's west wall. During the Roman-Persian Wars, siege warfare was extensively being used by both sides. Medieval period Arabia during Muhammad's era The early Muslims, led by the Islamic prophet Muhammad, made extensive use of sieges during military campaigns. The first use was during the Invasion of Banu Qaynuqa. According to Islamic tradition, the invasion of Banu Qaynuqa occurred in 624 AD. The Banu Qaynuqa were a Jewish tribe expelled by Muhammad for allegedly breaking the treaty known as the Constitution of Medina by pinning the clothes of a Muslim woman, which led to her being stripped naked. A Muslim killed a Jew in retaliation, and the Jews in turn killed the Muslim man. This escalated to a chain of revenge killings, and enmity grew between Muslims and the Banu Qaynuqa, leading to the siege of their fortress. The tribe eventually surrendered to Muhammad, who initially wanted to kill the members of Banu Qaynuqa but ultimately yielded to Abdullah ibn Ubayy's insistence and agreed to expel the Qaynuqa. The second siege was during the Invasion of Banu Nadir. According to The Sealed Nectar, the siege did not last long; the Banu Nadir Jews willingly offered to comply with the Muhammad's order and leave Madinah. Their caravan counted 600 loaded camels, including their chiefs, Huyai bin Akhtab, and Salam bin Abi Al-Huqaiq, who left for Khaibar, whereas another party shifted to Syria. Two of them embraced Islam, Yameen bin ‘Amr and Abu Sa‘d bin Wahab, and so they retained their personal wealth. Muhammad seized their weapons, land, houses, and wealth. Amongst the other booty he managed to capture, there were 50 armours, 50 helmets, and 340 swords. This booty was exclusively Muhammad's because no fighting was