Board Thread:Questions and Answers/@comment-24577079-20141203031648/@comment-24002937-20141207202907

How could you plausibly get a Jewish Rome? Judaism was far too much a tribal faith during the 1st millennium to really receive the number of gentile converts that could get them off the ground running in the Empire; and whilst they were quite widespread around the Eastern Mediterranean during the first century, their strict laws (no pork, circumcision, ect.) was to much for most potential male Greek and Roman converts (they did receive an number of widowed female 'converts' however), the demographic that they would need to win over if they ever were to take control of Rome itself.

Furthermore, whilst the diaspora spread them around the Empire greater than they ever had before, it was only following the fall of Jerusalem and the first Jewish-Roman war in which this occured, after such the Roman's pretty much viewed Jews as a beaten and broken people whose God had 'failed them', and with local anti-Jewish laws propping up around the turn of the 1st century the faith certainly wasn't planning on winning many more converts (indeed, towards the end of the offices' existence, the Kohen Godol and the high priests by a temporary ban on all gentiles converting to their faith). From then on out, those Jews that didn't convert away from their faith to Christianity (or one of the many cults appearing at the time) had to entretch what it meant to be a Jew, and that meant a stricter adherence to their laws (aka, the death nell the Jewish faith as a probable state religion for Rome).

In short, the only way to get a Jewish Rome is to illiminate the following points that made Judaism incompatiable with the later-Roman Empire;

Remember, Constantine didn't convert to Christianity in a vacuum; he did so at a time of great political, social, and religious strife, and so chose Christianity as it was one of the larger, more consolidating faiths of his time, coupled with the fact that it's central tenants could more easily be adopted and twisted by foreign cultures far than the tribalistic structure of Judaism ever could.
 * The majority of the faiths insistance on a strict interpretation and following of its laws (circumcision and the ban on pork being to surprisingly big ones);
 * The 'loss of prestige' the Jewish religion recieved on their defeat following the Jewish-Roman Wars and their subsequent diaspora;
 * The Kohen Godol's 'temporary' ban on the conversion of gentiles to Judaism.