What is the origin of the Catholic religion?

Answer 1

The Christian Church is thought to have started around 30-33 CE in the Near East, probably in Jerusalem. A second-century tradition claims that Peter went to Rome to lead the Church there, but there was already a Christian community in Rome during the time of the Apostle Paul, as we can see from his Epistle to the Romans. We do not know the origin of this community but, at this stage, the Roman church was not yet separate from the Church of the east.

The Catholic Church, as we know it today, originated from the Great Schism of 1054, when the Christian Church split to form the Catholic Church in the west and the Orthodox Church in the east.

Answer 2

I think it could be argued that the Roman Catholic Church has its origins in the establishment of the Vatican by the Emperor Constantine some time in the 300's.