In the beginning of the first century AD, the Roman Empire was just establishing itself and would soon be the largest empire the world had ever seen up to that point. It would stay this way for almost four hundred years, its citizens believing in three major religions: Christianity, Paganism and the Greek God's. Only one would endure, Christianity. .
In the third and fourth centuries AD the Roman Empire was going through a tough time. Its Economy was dwindling, Germanic tribes from the north were continually invading and new ideas were floating in the heads of its citizens. Most importantly that of religion. The Greek religions of old were that of the community while the new religions coming from eastern societies, were more individualistic, focusing as well on one almighty God. Among these new religions was Christianity. .
Christianity originated with the Jewish people in the Middle East, one text I read specifically said Palestine. Its founder was Jesus, an actual person unlike the Greek and Pagan god's. His life was documented in his biography, the four Gospels. In addition there were witnesses to his many miracles. Actual Fact that he had capabilities that where incomprehensible. Jesus was born poor; he worked as a carpenter before spreading his teachings and preached mainly to impoverished and less fortunate. Because of his back round and what Jesus preached (love, humanity, respect and equality of all people), the poor followed him; furthermore, most of the people of the time were poor (80-90%) so the religion soon had a considerable following. .
When Jesus died his Apostles, mainly St. Paul, started spreading Christianity in the Roman Empire. With its appeal to the lower classes as well as the upper crust, it spread across the Empire within a century, outlasting the older religions as well as the newer ones. .
In the year 313 AD, the Emperor Constantine took Christianity to the next level.