Well, the whole stable/cave and shepherd thing is reminiscent of certain version of the birth of Mithras, and Mithraism was Christianitys' biggest rival among the Romans.

The two stories also play into a notion I've long held that there were actually two men called Jesus who got conflated in the later stories.

In that case, we have Matthews' Jesus, a young Judaean of Davidian descent, visited by Magi and given expensive gifts, There's no evidence for Herods' Massacre (some say he was already dead by then), but a young princeling would very likely be sent to Alexandria in Egypt to study at the University there. Then the silly young lad becomes a Zealot terrorist and ends up getting crucified.

Lukes' Jesus is the son of a Galilean carpenter who was probably born in Nazareth - Luke changing the tale to fit the prophecies - and spent time with the Essene communty at nearby Khirbet Qumran. He later became an itinerant preacher, gathered a following, and went to Jerusalem where he caused a ruckus. The Temple priests were afraid that civil disorder might bring the Roman cohorts onto the streets, with bloody consequences. So they paid him a good chunk of silver to leave the city, using Judas as a go-between.. This Jesus either went back to the Essene monastery or, if he had a family (very likely) went to Alexandria, or they might even have settled in Massilia (modern Marseilles) where there was a thriving Jewish community.

All the Resurrection nonsense is likely Paul interpolating themes from local vegetation and mystery cults. Jesus, hanged and speared, is a Summer King while Judas, the Winter King, is sacrificed and disembowelled in an open field.