including the 'facts' about the lives of their teachers/saviors, and Christianity is a good example of that. Christianity used syncretism to gain converts and become the dominant religion in Europe and parts of western Asia. They realized that there were aspects of the various mystery religions and pagan myths that fed a psychological need that people had, possibly a need for explanation about the unknown, and the unknown covered a lot of ground in those days. So early Christians cobbled together elements of these different religions in order to gain converts, and the large number of converts gave them a lot more power, which was eventually put to use by kings and emperors to help control people.
Some people today think that Jesus the person was a complete fiction. I think there was an original teacher about whom the legend of Jesus is based, maybe even a few teachers who were in Palestine around the beginning of the Common Era. Of course I don't believe in the nativity story, and I'm not sure whether there was a crucifixion, although the idea of a teacher making Jewish leaders angry and running afoul of the Romans doesn't seem too farfetched.
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