@ JoC

Peter does have writings but I suspect you doubt their authenticity. Regardless, neither one is ever pointed out as the founder. Important leaders, yes. But founder(s), no, never. So what you're proposing is but speculation then.

There is considerable doubt that the "Peter" you would love to believe was Bishop of Rome ever existed. In fact, apart from a mention in Paul about a "Peter" in (bishop of?) Antioch there is no corroborating evidence at all of such a man.
You would have expected a mention of such an important personage in Paul's canonical letter to the Epistle to the Romans and especially in Chapter 16, which lists many people associated with the church there. Not even a passing mention. No mention in any Roman letters, no mention anywhere except in the gospels.
There is also considerable evidence that there was no position of "Bishop of Rome" until the late 2nd Century, well after the alleged crucifixion of Peter.
There is no evidence that "peter the apostle" (if he existed) was crucified upside down (which would have been a relatively humane and quick death within hours)

Even if one accepts the line that "Cephas" and "Simon Peter" and "Peter" are one and the same then other embarrassing contradictions raise their head, and there is still no contemporary third party evidence. Nothing.

We are back to claims in the bible that do not stand up to the barest modern historical scrutiny ....again.

Tradition has it that 1 Peter was the work of Peter. No evidence for that claim, only attribution by late 2nd century writers. . 2 Peter certainly is not as it the work of anonymous authors in the late 2nd Century CE. In addition the Gospel of Peter and the Apocalypse of Peter are not the work of the 1st Century and are anonymous, but probably written in the late 2nd Century as well.

In my estimation the "Cult of Peter" and probably the bulk of the biblical interpolations that support his supporters claims to be the "founder" of the Church and "leader appointed" were commenced in the mid 2nd Century ( when the Pauline Church was gaining ascendancy) and continued through until the establishment of the god emperor in charge of the church ...of course, in the name of Peter....

Seems to me to make a lot more historical sense and to clarify the claims of the Catholic Church that seized on the legend of Peter, it would certainly explain the interpolations In Matthew, Luke, John and Corinthians that the church relied on for centuries and have now been thought to be much later interpolations.

I think a couple of those verses do not even appear in later versions of non catholic bibles because of the doubts to their authenticity.

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