>>2913724>>2913651Also
>just spontaneously inventing a new version of their own religionThey didn't. Early Christianity bears significant similarities to the Essenes, a Jewish sect that preached pacifism, communal living, emphasized charity, and practiced baptism. This sect had existed for centuries prior to the emergence of Christianity.
>became based in Rome, didn't require circumcision or eschewing porkEarly Christianity wasn't based in Rome. Rather Rome was one of four major Christian centres that emerged in the first few centuries of its existence. The other three were Constantinople, Antioch, and Alexandria. Rome only increased in importance after the latter two were occupied by the Muslims, and Constantiople became the centre of a completely separate state following the collapse of the Western Empire. Even today, its really only of particular importance to Catholics.
Regarding the issue of pork, circumcision, and general adherence to Jewish law, this was actually a major point of contention among very early Christians. Paul and James argued about it frequently, with James arguing that followers of Jesus needed to strictly adhere to Jewish custom, and Paul (himself a Hellenized Jew) arguing that it was unnecessary. Given that Paul's version obviously appealed to more people, it's not surprising that it was more successful. The point though is that Christianity shedding its Jewish trappings wasn't predetermined, and was arguably the subject of the religion's first schism.
>Especially considering the military campaigns of Titus against the rebels in Judea parallels the life of Jesus in many strange waysThat probably has more to do with the literary traditions at the time, where the narratives of various "great men" followed a particular pattern according to established tropes. For example, Mesopotamian tradition holds that Sargon of Akkad was born in secret and placed in a basket in a river by his mother, not unlike the story of Moses.
>The alternative to recognizing that the gospels were written by Greek-speaking elites Based on the time period, Jewish elites being Greek speaking doesn't really indicate a connection to the Roman state. Greek had been established in the region as the language of literature, education, administration, etc. for centuries by that point. In fact it probably would have been unusual to find any educated, literate person who didn't speak and write it.