The Jews basically invented Christianity because they had been getting their asses handed to them by the Roman's and they needed some allies they could use as cannon fodder. The following article explains;
Recall that the Jews were a minority in Palestine at that time — as, of course, were the Romans. The majority consisted of the indigenous Palestinian masses, along with any incidental Egyptians, Syrians, Phoenicians, Persians, Greeks, and so on, who lived in the region. The masses were neither Roman nor Jewish. And of course, they weren’t yet Muslim; that religion would not exist for some 600 years. They would have adhered to a grab-bag of pagan traditions: Zoroastrianism, cults of Adonis and Mithras, Sibylline cults, and various sun-worshipping religions. These sects were generally ill-defined, superstitious, and highly mythological in nature.The Jews knew this. And they also knew that, in order to make an impact on Roman rule, they would have to get the superstitious masses on their side. But this was a big problem. The masses were not intrinsically anti-Roman. In fact, more likely the contrary. From their viewpoint, when the Romans moved in, it was more or less a change in government. And for the good: the masses generally disliked the Jews anyway, and the Romans brought with them many advancements in civilization. So the Jews had a big problem: How to win the masses over to their side, and turn them against Rome?Clearly they could not make them ‘Jewish.’ Judaism wouldn’t permit it, the ethnic and racial exclusivity of the Jews wouldn’t allow it, and the masses would never go for it, even if they could. All of Judaic tradition, from the Torah to the Talmud, was geared towards manipulating and exploiting the inferior Gentiles. The Jews would never have dreamt of mass conversion.Therefore, something else was required: a new way, a new outlook, a new worldview — something to subtly and perhaps subconsciously bring the masses into opposition with the Romans, and on the side of the Jews. Not Judaism, but something Jewish in essence. A new story, a new moral system, and yes, a new religion: Christianity.