The year is 525 CE. The place, Arabia, a land filled at that time with many idolatrous Arab tribes that were not yet united under the banner of one religion. To the northwest lies Bavel, where the Sasanian empire reigns over the Jewish community led by the Rabbanan Savorai, while to the northeast is Eretz Yisrael, where the Byzantine empire rules with an iron fist over the Jews whose leaders are the sages in Tiberias. Yet, astonishingly, in a place known as Himyar, a region in southern Arabia along the Red Sea coast, King Yussuf, a Jew, rules over a Jewish Kingdom. Who is Yussuf, and what are the origins of his kingdom?