Just outside the doors of the Colosseum is the Arch of Constantine. It was dedicated on 315 AD by the Senate to commemorate Constantine’s victory in 312 AD over Maxentius at the Battle of Milvian Bridge. The significance of this battle is that it ended the persecution of Christians. Let me back up… So, the night before the big battle, Constantine had a vision. In his vision, he saw the symbol of Christ with the words, “By this sign, conquer.” So, he had his men wear the symbol of Christ and he won the battle against a much larger army. As a result, Constantine adopted Christianity as his religion and ended the persecution of Christians.