Although initially pacified (the years between 7 and 26 CE being relatively quiet), the province continued to be a source of trouble under Emperor Caligula (after 37 CE). The cause of tensions in the east of the Empire was complicated, involving the spread of Greek culture, Roman law, and the rights of Jews in the Empire. Caligula did not trust the prefect of Roman Egypt, Aulus Avilius Flaccus. Flaccus had been loyal to Tiberius, had conspired against Caligula's mother and had connections with Egyptian separatists. In 38 CE, Caligula sent Herod Agrippa to Alexandria unannounced to check on Flaccus. According to Philo, the visit was met with jeers from the Greek population, who saw Agrippa as the king of the Jews. Flaccus tried to placate both the Greek population and Caligula by having statues of the emperor placed in Jewish synagogues. As a result, extensive religious riots broke out in the city. Caligula responded by removing Flaccus from his position and executing him. In 39 CE, Agrippa accused Herod Antipas, the tetrarch of Galilee and Perea, of planning a rebellion against Roman rule with the help of Parthia. Herod Antipas confessed and Caligula exiled him. Agrippa was rewarded with his territories.