The Banu Qurayza (Arabic: بنو قريظة, romanized: Banū Qurayẓa; alternate spellings include Quraiza, Qurayzah, Quraytha, and the archaic Koreiza) were a Jewish tribe which lived in northern Arabia, at the oasis of Yathrib (now known as Medina). They were one of the three major Jewish tribes of the city, along with the Banu Qaynuqa and Banu Nadir. Jewish tribes reportedly arrived in Hijaz in the wake of the Jewish–Roman wars and introduced agriculture, putting them in a culturally, economically and politically dominant position. However, in the 5th century, the Banu Aws and the Banu Khazraj, two Arab tribes that had arrived from Yemen, gained dominance. When these two tribes became embroiled in conflict with each other, the Jewish tribes, now clients or allies of the Arabs, fought on different sides, the Qurayza siding with the Aws. In 622, the Islamic prophet Muhammad arrived at Yathrib from Mecca and reportedly established a pact between the conflicting parties. While the city found itself at war with Muhammad's native Meccan tribe of the Quraysh, tensions between the growing numbers of Muslims and the Jewish communities mounted. In 627, when the Quraysh and their allies besieged the city in the Battle of the Trench, the Qurayza initially tried to remain neutral but eventually entered into negotiations with the besieging army, violating the pact they had agreed to years earlier, the Constitution of Medina. Subsequently, the tribe was charged with treason and besieged by the Muslims commanded by Muhammad. The Banu Qurayza eventually surrendered1 and their men were beheaded.1 The historicity of this incident has been questioned by Islamic scholars of the Revisionist School of Islamic Studies and by some Western specialists.