On this day 1699 years ago, Flavius Valerius Constantius enters the city of Rome after defeating his rival Maxentius at the Milvian Bridge.
This was part of the War of the Tetrarchy, which lasted from 306-324 AD. It was the direct result of the recently deceased emperor, Diocletian. He divided his territory into two subdivisions. By 306, the men he chose for this task had further broke down the Empire and appointed two other rulers. Now there were four men who held the title Caesar. Constantine's father, Constantius Chlorus, was one of them. This was done to prevent a repeat of the Crisis of the Third Century, during which more than 50 aspiring emperors were appointed and killed. However, as in the days of Pompey Magnus and Julius Caesar, and the days of Octavian and Mark Antony, shared power never lasted long in Rome.
In 306, Constantius died in what is now York. His legions proclaimed Constantine as emperor. This caused Maxentius to make the same declaration and moved into the Rome itself. Constantine knew that to secure his dominance of the West, he had to take the city. On October 27, two days before battle, the general and his men beheld a sign in the sky. It was a large X with a center spike and a rounded P shape. This has been argued to represent the crown of thorns. At any rate, accounts of the symbol have been disputed for centuries. But one thing was clear, on the day of the battle, Constantine's soldiers appeared with a standard that no one had seen before.
Maxentius' men tried to lure Constantine across the bridge, which was rigged to collapse. He didn't take the bait. Rather, he sent his cavalry in front, which broke the horsemen of the enemy and sent the infantry fleeing. Maxentius tried to go with them, but was pushed into the river and drowned. The battle was bloody and brief. His severed head was sent to Carthage, and ensured that Rome's ancient enemy wouldn't attempt to gain independence.
The Western half was now secure. Only two rivals remained: Maximian Daia and Licinius. The war would be over by 324. During his reign, Constantine would write the Edict of Milan, outlawing the persecution of all Christians.
