Constantine the Great, also known as Constantine I, was born about A.D. 275 and died in 337. During his reign Christians regained freedom of worship, and Christianity became a legal religion in the Roman Empire. He rebuilt Byzantium (now Istanbul), renamed it Constantinople, and made it his capital. He shifted the Roman Empire's strength from Rome to the eastern provinces and thus laid the foundations of the Byzantine Empire.
In A.D. 312 the People and Senate of Rome, in honor of the Emperor, erected the Arch of Constantine in the great Square of the Colosseum in Rome. Constantine had liberated the city and the state from the tyrant Maxentius by his victory in the battle of Milvian Bridge. The arch is decorated with sculptures taken from earlier monuments erected by Trajan, Hadrian and others, and only the small reliefs which run around the monument actually depict events from the life of Constantine.