305              Diocletian and Maximian resign as co-emperors

306              Constantine named emperor in the west by his troops

312               Constantine defeats Maxentius at the Milvian Bridge

313               Constantine and Licinius declare the Edict of Milan

324              Constantine defeats Licinius and reunites the empire

325              Council of Nicaea produces the orthodox doctrine of Nicene Christianity

330              Constantinople consecrated as the new capital of the empire

337               Death of Constantine; Constantius II initially co-emperor

353              Constantius II defeats Magnentius and becomes sole emperor

361               Death of Constantius II; accession of Julian the Apostate

363              Death of Julian the Apostate

c. 370          Arrival of the Huns in Europe

376              Valens allows 100,000 Visigoths to settle in Moesia as federates of the Roman army

378              Visigoth federates defeat Romans at the battle of Adrianople; death of Valens; accession of Theodosius I in the east

380              Nicene Christianity declared the sole religion of the empire

382              Theodosius I makes peace with the Visigoths and allows them to be full members of the Roman army

393              Theodosius I defeats the western emperor Eugenius with help from Visigoth forces led by Alaric; pagan ceremonies outlawed

395              Death of Theodosius I; accession of Honorius in the west and Arcadius in the east