Famous Jews in the Roman Empire

I doubt that would have been possible. Public office at this level required participation in religious rites that traditional jews would have been forbidden from, both prior to 312 and after 395, and I doubt the climate was all that favourable inbetween.
 
There was Tiberius Julius Alexander, although one could argue about how Jewish he really was. Schoenfeld's article on Jews in the legions mentions several who held high rank in the military or in provincial administration, although none who served as senators or consuls. I'd guess that a provincial governorship was as high as Jews could rise at that time, given the religious obligations that carlton_bach mentions.
 
Um... Josephus?

Never held any formal rank. There were loads of prominent and influential Jews, starting (obviously) with Herod and his kin. But the question here is Jews who held high rank in the formal structure of the Roman state. That's very hard to see, at least for Jews that would be universally accepted as Jews by the community (mind, Herod certainly wasn't, and I'm not sure where Josephus stood with the more traditional Jews after 70).
 
Were there any converted Jews (converted to Roman Paganism or Christianity), beside Tiberius Alexander, who held high rank (se above) in the formal structure of the Roman state?
 
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