Some people hold up Mithras as a very close parallel to Jesus. They will point out that Mithraism and Christianity were competing religions at the same time in the Roman Empire.
That is true, although they were appealing to completely different crowds. Mithraism was popular among soldiers, which was not the case for Christianity.
There is also the problem that the evidence we have for the Roman Mithras (as opposed to the earlier Persian and Indian versions) actually post-dates the Gospels, making it difficult for them to be a source.
I put together this graphic to point out that the parallels between Mithras and Jesus are not very strong.
