Around A.D 285 Diocletian became the Roman emperor.  He realized that the empire had grown too large to be governed by one person.  He divided the kingdom into two (East and West).  He kept the ultimate power and appointed governors and assistants.  In the West, they were Maximian and Constantius.  We all have heard about the Holy Roman emperor Constantine.  Constantine was the son of Constantius.  Around A.D 303 Diocletian issued edicts banning Christianity.  In the Eastern part of the empire churches were destroyed and many Christians were martyred.  In the West, Constantius didn’t enforce the ban strictly.  I believe it could be due to St. Helena, Constantine’s mother who was sympathetic to Christianity.  Diocletian retired in A.D 305 making Galarius, his assistant as the emperor of the East.  Galarius continued to persecute Christians and fell ill in a few years.  When he was on the deathbed, he issues an edict pronouncing that the God of Christians is the true God.  He asked Christians to pray for his recovery.  After his death, however, the persecution continued. After the death of Constantius, Constantine was made the emperor of the Western empire.  Maximian’s son Maxentius resisted Constantine and there was civil war between them which is known as the battle of Milvian bridge over the river Tiber.  Just before the battle started, Constantine saw a vision of a Christian symbol

.   These are two Greek letters imposed on each other.  The letter Chi (looks like X) and the letter Rho (looks like P) are the first two letters of Christos in Greek.  There are some versions of this story that says Constantine saw a Cross in his vision.  Constantine won the battle, and the success is attributed to his vision.  He became emperor of the Western empire.  In A.D 313 Constantine issued the edict of Milan which legalized Christianity.  Crucifixion was ended as a form of death penalty.  Sunday was made a day of rest.  The emperor, influenced by the Catholic Church, has started to make social changes in the society.  Emperor Constantine wanted to make Christianity the only religion in Rome, but the senate had several influential pagans.  What did Constantine do?  He moved the capital to present day Turkey’s Istanbul and named it Constantinople.  He didn’t allow any pagan icons in Constantinople.  It should be noted that Constantine with all this piety didn’t choose to get Baptized into the Church.  He was Baptized on his death bed.  Constantine realized that unity in the Church is essential for the unity of Roman empire.  There were, however, couple of controversies that were threatening such a unity that he desired.  They were Donatism and Arianism.