Who was the first Roman Emperor to establish Christianity as the official religion of the empire?

Answer 1

Answer

The evidence is mixed on which Roman emperor could be said to be the first to allow Christianity. The following is an incomplete selection of those who could claim to be the first emperor to allow Christianity. The inclusion of Nero would be controversial because of Christian traditions of widespread and severe persecution that grew up in the following centuries, but this list is based on known facts, not traditions.

Nero (54-68 CE) is said to have blamed the Christians of Rome for the Great Fire and persecuted them for this crime. However, he must have known of the Christians in Rome long before the Great Fire and apparently made no attempt to ban them. Moreover the punishment of the Christians was limited to Rome, with no evidence of any persecution or ban outside Rome.

Trajan (98-117) said that Christians were not to be sought out for punishment, effectively a statement allowing Christians to coexist with pagans. He prohibited his magistrates from making any inquiries and rejected anonymous charges against the supposed criminals. The correspondence between Trajan and Pliny the Younger suggests that no previous emperor had publicly declared any intentions concerning the new sect and that, whatever legal proceedings had been carried on against the Christians, there were none of sufficient weight and authority to establish a precedent for the conduct of a Roman magistrate. Before the time of Trajan, Christians seem to have simply been ignored unless they disturbed the peace by their conduct.

Hadrian (117-138) went further than Trajan, decreeing that those who made failed allegations of Christianity in court, would face capital punishment. Since Trajan had ruled that magistrates could only proceed on the basis of a public allegation, this largely freed Christians from any risk of prosecution for Atheism.

Commodus (180-192) clearly allowed Christians, since his favourite concubine declared herself the patroness of the Christians.

Philip (244-249) was so well disposed to Christianity that it was rumoured that he himself was a Christian, a debate that has still not been settled.

Finally, Constantine (306-337) not only allowed Christianity, but favoured it and began a long period of persecution of paganism. He sought to ensure that Christianity would actually replace the ancient pagan religions.

Answer 2

Emperor Constantine, who also eventually changed the capitol to the city of Byzantium and changed the cities name to Constantinople. Just a slight clarification here. Constantine never made Christianity the official religion of the empire. All he did was make Christianity a legal religion. It was the emperor Theodosius I, in 380 Ad, who made it the official religion.

Answer 3

Athough Chrisitanity was persecuted several times during the Roman Empire, it was never actually illegal. In 380 the co-emperors Theodosius and Gratian issued the Edict of Thessalonica which made mainstream Christianity (the Latin and Greek Churches, which later came to be called Catholic and Orthodox respectively) the sole legitimate religion of the empire. Christianity became state religion.. The object of the edict was to ban the many dissident Christian doctrines which were branded heretic. The main target was Arian Christianity, which was popular around the empire and which was persecuted.