[ealgeone]

Irenaeus of Lyons says that the church at Rome was "founded and organized" by Peter and Paul. He was a good bit closer to those events than you are, and lived well before those amazing events "around the 4th century" that you're going to specify for us, dying around AD 150.

Gonna need more than one source on this one. Too many conflicting positions. No mention by Paul of Peter while he was in Rome or any credit given to Peter on this.

[Campion]

Irenaeus said it. Eusebius gives details. Ignatius of Antioch (Epistle to the Romans) says he does not command the Romans as Peter and Paul did.

There are many other examples.