The doctrines of Petrine primacy and papal primacy are perhaps the most contentiously disputed in the history of Christianity. Theologians regard the doctrine of papal primacy as having developed gradually in the West due to the convergence of a number of factors, e.g., the dignity of Rome as the only apostolic see in the West; the tradition that both Peter and Paul had been martyred there; Rome's long history as a capital of the Roman Empire; and its continuing position as the chief center of commerce and communication.