Happy Milvian Bridge Day

From "The Battle of the Milvian Bridge" by Giulio Romano.

Today is the anniversary of the Battle of the Milvian Bridge in 312 between the Roman Emperors Constantine I and Maxentius. 

The battle, won by Constantine, was notable in that Constantine attributed his victory to the Christian god and subsquent legalization of the Christian faith in 313, thus ending the persecution of Christians in the empire.