They did not belong to the Christian Eastern Orthodox faith, which was the state church of the Byzantine Empire, nor were they, in most circumstances, grouped together with heretics and pagans.
The place along the spectrum of social freedom in which Byzantine Jews found themselves varied somewhat, though far from drastically, with time, and depended largely on three factors: the theological desire of the state to maintain Jews as a living testament to the victory of Christianity, the desire of the state to strengthen its control, and the ability of centralized rule from Constantinople to enforce its legislation.
[2] Indeed, Jews enjoyed the right to practice their faith under the rule of the Byzantines, as long as they paid the Fiscus Judaicus.
[7] Thus Emperor Theodosius II found that he had to balance the first two of the three factors governing the treatment of Jews in the empire—theology, political pragmatism and enforceability.
Theodosius II, who laid out much of the legal precedent and foundation for Byzantine law in his Theodosian Code, permitted Jews, like other citizens, to hire a substitute to perform the duties of decurion in their place.
[5] Justinian, whose legal code included 33 laws relating to the Jews,[10] initially maintained this ability, but it was abolished in 537.
This prohibition was difficult to enforce, as archaeological evidence in Israel indicates that illegal synagogue construction continued throughout the sixth century.
Beginning at this time, most legislation regarding the Jews—even laws which expanded the rights which they were afforded—were "prefaced by unambiguous expressions of hatred and contempt for Judaism".
[16] In fact, Justinian banned all non-Christian places of worship in northern Africa, in legislation that grouped Jews with pagans and heretics.
For instance, Justinian demanded that Passover be shown as subservient to Easter; in cases in which the former would fall before the latter, the Jews were forbidden from celebrating it on its appointed day, and were compelled to delay it.
[16] Once more, the state sacrificed the doctrinal subordination of the Jews in order to gain practical benefits, in this case testimony against those who faced it in court.
However, during the Byzantine–Sasanian War of 602–628 many Jews sided against the Byzantine Empire in the Jewish revolt against Heraclius, which successfully assisted the invading Persian Sassanids in conquering all of Roman Egypt and Syria.
Eleazar ben Killir a Byzantine Jew from a Greek-speaking area wrote his famous piyutim, which are still in use in the most Machzorim and became the teacher of all paytanim who came after him.
Judah Leon ben Moses Mosconi, a Romaniote Jew from Achrida edited and expanded the Sefer Josippon later.
[39] It was in the 12th century that the passing Crusaders wrought havoc upon the Jewish communities of Byzantium, in a foretaste of what the later Latin occupation would bring upon the Byzantine Christians.
Theodore Doukas, who crowned himself emperor of Epiros after he conquered Thessalonica, was known for his persecution of the Jews, which began in 1229, a year before the end of his reign.
[42] Although these measures began only a year before Vatatzes' death, they seemed to have set a precedent of persecution which his son, Theodore II Laskaris, followed.
Additionally, he oversaw an empire which was strongly dependent on foreign powers, and had an immense need for gold to fund its great military expenses.
It is not surprising, therefore, that he turned to the Jews and other minorities (most notably the Armenians) as a source of support in an embattled state of affairs, and when the ethnic majority and the mainstream elite had grown unfriendly toward him.
[44] The patriarch's complaint indicates that, in spite of the tolerance of the Palaiologoi, the norm of imperial law was to require non-Christians to live separately from Christians.
This apparent trend of segregation between the peoples of Byzantium, which certainly included the Jews, is confirmed in a letter by John, bishop of Citrus, in the latter half of the twelfth century, which declared that, "People of alien tongues and alien beliefs, such as Jews, Armenians, Ishmaelites, Hagarites and other such as these were permitted from of old to dwell in Christian countries and cities, except that they had to live separately and not together with the Christians".
[48] At this time, the Empire was in rapid decay, and could not seriously enforce laws intended to curtail these rights and regain economic control within its borders.
Thus, an exception to the general trend of Byzantine history emerged during this century, whereby Jews were entitled to a broader set of rights than Christians.
Non-Venetian Jews did not profit from the Venetian-Byzantine treaties, and non-Jewish Venetians enjoyed the same liberties as their Jewish compatriots.