Eleazar ben Yair

The Sicarii (Modern Hebrew: סיקריים siqari'im) were a splinter group of the Jewish Zealots who, in the decades preceding Jerusalem's destruction in 70 CE, heavily opposed the Roman occupation of Judea and attempted to expel them and their sympathizers from the area. The Sicarii carried sicae, or small daggers, concealed in their cloaks. At public gatherings, they pulled out these daggers to attack Romans and Hebrew Roman sympathizers alike, blending into the crowd after the deed to escape detection.

The Sicarii were likely one of the earliest forms of an organized assassination unit of cloak and daggers, predating the Islamic Hashishin and Japanese ninjas by centuries.

In Latin, Sicarii is the plural form of Sicarius "dagger-man", "dagger-wielder". Sica here comes from the root , "to slice". In later Latin usage, "sicarius" was also the standard term for a murderer (see e.g. the Lex Cornelia de Sicariis et Veneficiis).

Victims of the Sicarii included Jonathan the High Priest, although it is possible that his murder was orchestrated by the Roman governor Antonius Felix. Some murders were met with severe retaliation by the Romans on the entire Hebrew population of the country. On some occasions, the Sicarii could be bribed to spare their intended victims. Once, Josephus relates, after kidnapping the secretary of Eleazar, governor of the Temple precincts, they agreed to release him in exchange for the release of ten of their captured assassins.

At the beginning of the First Roman-Jewish War, the Sicarii, and (possibly) Zealot helpers (Josephus differentiated between the two but did not explain the main differences in depth), gained access to Jerusalem and committed a series of atrocities in order to force the population out of docility and into war against Rome. In one account, given in the Talmud, they destroyed the city's food supply so that the people would be forced to fight against the Roman siege instead of negotiating peace. Their leaders, including Menahem ben Yehuda and Eleazar ben Ya'ir, were important figures in the war, and the group fought in many battles against the Romans as soldiers. Together with a small group of followers, Menahem made his way to the fortress of Masada, took over a Roman garrison and slaughtered all 700 soldiers there. They also took over another fortress called Antonia and overpowered the troops of Agrippa II. He also trained them to conduct various guerrilla operations on Roman convoys and legions stationed around Judea.

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