the council of nicea part is a little hard to swallow
tons of evidence Christianity existed before 325 AD, so... can't really swallow this.
fwiw, I think a lot of the reasons you have overlap in ancient religions is not just the trading of ideas but the generally shared experiences of early human cultures. things like flood myths make a lot more sense when you realize that most early civilizations were built on fuging flood plains.
Yeah, I feel rather foolish now.
Read the OP.
Accepted the information on faith without any effort to compare it to verifiable historic or scientific evidence.