Into the Amalekite town of Yathrib, Jews likely arrived sometime between the era of Moses and the Babylonian captivity. By the fourth century, Arab tribes began to encroach from Yemen, and there were three prominent Jewish tribes that inhabited the city into the 7th century AD: the Banu Qaynuqa, the Banu Qurayza, and Banu Nadir.[12] Ibn Khordadbeh later reported that during the Persian Empire's domination in Hejaz, the Banu Qurayza served as tax collectors for the shah.[13]