I rather wonder why you think so, except some vague assumption that it couldn't *possibly* be true simply because it is has been maintained for 2000 years straight.
There is of course, no question that the Romans and the Etruscans borrowed many practices. Or that Romans buried their dead in necropoli (I have, in fact, been to the most famous Etruscan one at Cerveteri).
But what that has to do with St. Peter being a myth, I have no idea. To say nothing of the NT, the historical sources--*from the 2nd century* are unanimous in putting Peter in Rome. We have found his name scratched on graffiti in that necropolis below the cathedral.
Do you expect us to believe that an entirely different person of an entirely different name--both lost to history--headed the Christian community in Rome? A person apparently totally forgotten by everyone? And instead the Christian writers of the 1st and second century, who could name the succession from Peter to Linus to Clement and on, (oops!) just accidentally ascribed the founding to a made-up Galilean fisherman?
*Sigh*...how I tire of this modern fetish of "debunking".
You beat me to it!
I'm an agnostic who has no dog in this hunt, but the comments weren't that Peter wasn't the head of the church in Rome, but that he wasn't considered the head of the movement after the death of Jesus.
As an agnostic, but a historian, I'm always open to new scholarship on the historical proofs of religion. I recently read "the Jesus Dynasty" which has some very interesting scholarship. Here are some excerpts found at:
http://www.jesusdynasty.com/Exerpts-from-James-Tabors-Jesus-Dynasty.html
Jesus' successors and legacy:
"Although the followers of Jesus reshaped themselves under the new leadership of James, and eventually returned to Jerusalem, there might well have been a period in which they retreated to Galilee in order to sort things out, and that is just what these gospel traditions appear to reflect. If that was the case then the more idealized account of the Jesus movement in the early chapters of the book of Acts is Luke' s attempt to recast things in a more triumphant way." (p. 238)
"There are two completely separate and distinct 'Christianities' embedded in the New Testament. One is quite familiar and became the version of the Christian faith known to billions over the past two millennia. Its main proponent was the apostle Paul. The other has been largely forgotten and by the turn of the 1st century A.D. had been effectively marginalized and suppressed by the other." (p. 259)
"The Nazarene movement, led by James, Peter, and John, was by any historical definition a Messianic Movement within Judaism. Even the term 'Jewish-Christianity,' though perhaps useful as a description of the original followers of Jesus, is really a misnomer since they never considered themselves anything but faithful Jews. In that sense early Christianity is Jewish." (p. 264)
"I would go so far as to say that the New Testament itself is primarily a literary legacy of the apostle Paul." (p. 270)
"There is no evidence that James worshipped his brother or considered him divine." (p. 280)
"...[W]hat we can know, with some certainty, is that the royal family of Jesus, including the children and grandchildren of his brothers and sisters, were honored by the early Christians well into the 2nd century A.D., while at the same time they were watched and hunted down by the highest levels of the Roman government in Palestine." (p. 290)