Ideas and power

Some notes on the conversion of Constantine:

In the third century, the Roman Empire is restructured to meet the Persian threat. The armed forces and the imperial bureaucracy grow. The Imperial office is split. The Empire becomes more intrusive and more committed to an ideological stance.

Polytheism very varied -- every region has its own religious traditions. Cults do not ask for very much: demand that respect is paid to the spirits protecting the region, that rituals are performed properly. Philosophical and moral answers are looked for elsewhere.

Christianity doesn't penetrate very far into society. But isn't (in theory) local. An Empire-wide phenomenon. One God that demands exclusive devotion. Scriptures that contain universal code of law.

Laws of the Emperor regarded as the source of all order. Christian claims to the contrary are subversive. Christian attacks on idol-worship also subversive. Emperors had to demonstrate that they are acting against 'impiety', and the Church is the obvious target. Sporadic local anti-Christian violence gives way to Empire-wide edicts in 250 and 257. Diocletian's 'Great Persecution' in 303 continues for 11 years in some parts of the eastern Empire. But the religion proves difficult to suppress.

Constantine wins the battle of the Milvian Bridge in 312, and says his success is due to the protection of the God of the Christians. Why? Perhaps the faith fitted well with the new shape of the Empire -- more bureaucratic and integrated than before. The regional differences in religious tradition could prove divisive. Christianity wasn't regional. Based in the cities and had wealthy, educated and commited followers. It was a good pick for a new, unified, Imperial faith?

Council of Nicea called by Constantine in 325 to straighten out divergent practices. Uniformity was the key. Around 200 bishops attend, but the Emperor has the final say. Arianism condemned. However Constantine fetched Arius back from exile in 328, and had two other councils in 335 declare him an orthodox Christian.

Emperors liked Arianism because it limited Christ's role to that of another prophet, and allowed Emperors to assume an equal status -- living prophets directing the course of their church. Anti-Arian ideologies were formulated partly as a reaction against such interventionism. Carried the day at Nicea, but there would be a lot of centre-local conflict over it in future centuries. See here.