Generally, the imperial period, the Roman state was tolerant of all religions, but only on two conditions: 1) that they would accept the cult of the emperor (not so the rebellion), 2) that he had not exclusive of other religions (not then to monotheism). The state in fact wanted to influence through their own gods and customs of the conquered peoples, until you get to a certain cultural assimilation, legal, political and even religious (Zeus greek, e.g. He identified with Jupiter, the Carthaginian Baal with Saturn, Mars Teutate of the Gauls, and so on). The city of Rome was to be regarded as a deity in the provinces. This conditioning, in the western provinces, characterized by most primitive religions of the Eastern Churches, the Roman state could with relative ease.
Discussion
The Jews, so strictly monotheistic, were the exception that proves the rule, but only because their religion was little heard from the pagan world (it was ethno-nationalist), also because he was not proselytizing or, if he did, did not meet many followers , especially among the male (think obstacle of circumcision). The Jews (as a religious group) practically lived secluded from the Roman world (they were the only ones to reject intermarriage). Themselves, on the other hand, they felt "different" from others (think e.g. the detailed dietary laws). When he organized the imperial cult, the Jews were exempt from this requirement, but since this concession resulted in an increase in the financial burden on other subjects, they were obliged to contribute to the Treasury with a daily sacrifice offered to God on behalf of their sovereign. Caligula's attempt to challenge this modus vivendi, forcing Jews to apostatize, but Claudio will raise him up.
Anyway, the Jews were often subjected to waves of anti-Semitism, because the ...