Battle of Milvian Bridge — Constantine's Vision
Constantine defeated Maxentius at a bridge over the Tiber on 28 October 312 and became a Christian emperor. The empire had been divided since Diocletian's tetrarchy into a system of senior and junior rulers that was supposed to prevent civil war and instead multiplied the number of claimants. By 312 there were four, and Constantine invaded Italy from Gaul with a smaller army against Maxentius, who held Rome and had beaten off two previous invasions by sitting behind the Aurelian walls. This time he came out. The reason is unclear and probably combined the Sibylline books, the anniversary of his accession, and a grain riot in the city. He drew up with the river behind him, having broken the Milvian bridge and replaced it with a pontoon, which left no line of retreat when his line gave way. He drowned in the Tiber in the crush. The vision is what everyone remembers. Lactantius, writing within a few years, says Constantine was told in a dream to mark his soldiers' shields with a sign; Eusebius, decades later, has him and the whole army see a cross in the sky with the words by this conquer. The two accounts do not agree and both come from Christian authors close to him. He entered Rome, declined to sacrifice on the Capitol, met Licinius at Milan the following February, and began forty years of imperial patronage that made a persecuted minority the state religion. Maxentius had also been the last emperor to reside in Rome. Constantine built a new capital on the Bosphorus within twenty years, and the city that had given the empire its name became a ceremonial place its rulers rarely visited.
- Year: 312 CE
- Category: Military
