I have done a bit of reading about both Judaism and the Roman Empire, and I found it surprising that Jews were afforded distinct statuses under the Romans, especially considering Jews were a small, relatively uninfluential people group at the time. Some of the legal distinctions I am referring to include:

• Jewish exemption from the Roman Imperial Cult
• Fiscus Judaicus, the "Jewish tax"
• Jewish exemption from the Roman military (because of shabbat observance? or as thanks for helping Julius Cesear?) though is this even true?
• In Roman Egypt, aside from the colonial identities of "Greek" and "Roman" and the catch-all category of "Egyptian" (which basically included everyone else), "Jew" was the only distinct social status recognized in the province

My first question is to what degree were these sorts of arrangement with particular people groups exceptional? I.e. did the Romans commonly make these sorts of compromises with distinct people groups?

My second question is what prompted such distinctive treatment of the Jewish people by the Romans? This question is mainly concerning the latter two of my above points (rather than the first two, which I understand to have been the consequences of the Jewish-Roman Wars). I.e. why were Jews exempted from Roman military service (if this is even true), and why were "Jews" the only non-colonial, non-indigenous identity legally recognized in Roman Egypt?