In the early 11th century, centralized authority based at Cordoba broke down following the Berber invasion and the ousting of the Umayyads. In its stead arose the independent "taifa" principalities under the rule of local Muwallad, Arab, Berber, or Slavonic leaders. Rather than having a stifling effect, the disintegration of the caliphate expanded the opportunities to Jewish and other professionals. The services of Jewish scientists, doctors, traders, poets, and scholars were generally valued by Christian and Muslim rulers of regional centers, especially as order was restored in recently conquered towns. Rabbi Samuel ha-Nagid (ibn Naghrela) was the Vizier of Granada. He was succeeded by his son Joseph ibn Naghrela who was slain by an incited mob along with most of the Jewish community. The remnant fled to Lucena.