Anti-Christian policies in the Roman Empire

Persecution of Christians in the Roman Empire occurred intermittently over a period of over two centuries until the year 313 AD when the Roman Emperors Constantine the Great and Licinius jointly promulgated the Edict of Milan which legalised the Christian religion. The persecution of Christians in the Roman Empire was carried out by the state and also by local authorities on a sporadic, ad hoc basis, often at the whims of local communities. Starting in 250, empire-wide persecution took place by decree of the emperor Decius. The edict was in force for eighteen months, during which time some Christians were killed while others apostatised to escape execution.

These persecutions heavily influenced the development of Christianity, shaping Christian theology and the structure of the Church. Among other things, persecution gave rise to many saints' cults which may have contributed to the rapid spread of Christianity and sparked written explanations and defenses of the Christian religion.

Persecution of the early church had occurred sporadically and in localised areas since its beginning. The first persecution of Christians organised by the Roman government took place under the emperor Nero in 64 AD after the Great Fire of Rome. With the passage in 313 AD of the Edict of Milan, persecution of Christians by the Roman state ceased. The total number of Christians who lost their lives because of these persecutions is unknown; although early church historian Eusebius, whose works are the only source for many of these events, speaks of "great multitudes" having perished, he is thought by many scholars today to have exaggerated their numbers.

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