The Sicarii and the Zealots are two groups of Jewish militants, hostile to Rome, who were active in first-century Judaea. The historian Flavius Josephus presents them very negatively as he attributes to them a great deal of the responsibility for the first Jewish Revolt (66 CE – 73 CE), which was fatal to the aspirations for the independence of the Jewish nation. Modern historians, who see them as “pious assassins”, have often conflated the two groups. In actuality, although they shared the nationalistic views of the "Fourth Philosophy," which first appeared in 6 CE, they are distinct. Only the Sicarii [so called by the Romans, who considered them bandits] practiced urban terrorism against their fellow countrymen accused of collaborating with the Roman authorities. The Zealots (who gave this name to themselves to emphasise their zeal for God) were young Jerusalemite priests who refused allegiance to Rome. Both groups played a role in triggering the Revolt — the Sicarii by taking over the Masada Fortress in 66 CE which they continued to hold until 73 CE as the last outpost of Jewish resistance, and the Zealots by refusing to accept the sacrifices offered to the Temple by the Roman emperor.