In Matthew chapter 16 verse 18 Jesus said to Peter, You are the rock on which I will build my church. The early christian church was socialist, and Acts 5 describes a couple called Ananias and Saphire who sold their property in order to give to the church, but kept back part of the money. According to the text, they were confronted by Peter, died instantly after lying about the full proceeds from the sale and great fear seized the whole church so no one else dare join them.
Paul came to leadership. He was a pharisee and the son of a pharisee though his mother was unknown. In the biblical text, during the greek empire there was a policy of intermarriage and he is believed to have had greek connections, but was a roman citizen by birth, a status giving him unique rights and protections. He is documented to have persecuted the early church before joining it and becoming leader.
The roman emperor became christian following a battle for leadership between emperor Constantine the great and his rival Maxentius. According to the story, preceding the battle, Constantine thought he could see the letter P intersecting an X, generally believed to mean Peter died, on each of his soldiers’ shields. He decided that he would become christian if he won. He did and the church became suzerain