trajan
Emperor Theodosius banned public worship in pagan temples in 391 CE. In 395, his Theodosian Code included the following: "We decree that no one shall have the right to approach any shrine or temple whatsoever, or to perform abominable sacrifices in any place or time whatsoever. All persons, therefore, who try to deviate from the dogma of the Catholic Church shall hurry to observe ...". The penalties could be the confiscation of land and property, or even execution.
As a consequence of the edicts of Theodosius, open persecution of pagans began in earnest. Some fled, some converted and others adapted their paganism to be less offensive to their Christian opponents. Open defiance in Alexandria led to the ancient library being burned, along with its priceless collection of books. Pagan worship clung on tenaciously, but had completely ceased in urban areas by the eighth century.
Emperor Theodosius (378-395) made Christianity the official religion of empire in 380 CE, and in 391 made it illegal to worship the pagan gods in public: "It is Our will that all the peoples who are ruled by the administration of Our Clemency shall practice that religion which the divine Peter the Apostle transmitted to the Romans. According to the apostolic teaching and the doctrine of the Gospel, let us believe in the one deity of the father, Son and Holy Spirit, in equal majesty and in a holy Trinity. ... The rest, whom We adjudge demented and insane, shall sustain the infamy of heretical dogmas, their meeting places shall not receive the name of churches, and they shall be smitten first by divine vengeance and secondly by the retribution of Our own initiative."
In the words of Edward Gibbon: "The ruin of Paganism, in the age of Theodosius, is perhaps the only example of the total extirpation of any ancient and popular superstition, and may therefore deserve to be considered as a singular event in the history of the human mind."
Some of the decrees of Theodosius:
Even at the height of the "Great Persecution" of 303-311, the Christians were shown more tolerance and clemency than Theodosius now showed the pagans.
Christianity was outlawed in Rome during the reign of Nero. Exact dates unknown
Emperor Constantine I issued a law demanding religious tolerance of Christians. Once Christianity took hold, of course, they turned the tables and persecuted pagans.
Christian were often charged under the law of maiestas having to do with honoring the Emperor. I don't see any law which specifies Christianity at least in the first century
Constantine I
Persecution of Christians, and maybe some others.
He ended the persecution of Christians
Approximately three centuries
Possibly, he stopped the persecution of Christians in Rome, but that may have been just to get their support in battle
The Emperor Constantine made these changes.
Yes they did in secret rooms in their house
After the Great Fire of Rome, in the year 64, Emperor Nero did, perhaps unfairly, blame the Christians of Rome for starting the fire. However, there is no evidence that he persec uted the Christians more generally.
There was a persecution of Christians in the city of Rome in 64 AD. However, it was not an official persecution and it was not legislated. According to Tacitus, a Roman historian, the emperor Nero used the Christians and a scapegoat because there were allegations that he started the Great Fire of that year.
Nero did not "start a campaign against the Christians." In the aftermath of a devastating fire in Rome in 64 AD, rumor had it that Nero had started the fire. To shift suspicion away from himself, he began arresting Christians. Some of those arrested informed against others and, for a few weeks in the city of Rome itself, Christians were tortured in particularly barbaric ways. The historian Tacitus, in his Annals 15.44, describes the persecution and says that the ferocity of it soon created a backlash of sympathy for the Christians. This persecution was short-lived and did not spread beyond the city of Rome.
It appears from historical evidence that the early Christians were largely ignored by the pagan Roman Empire, apart from two brief periods of official persecution after 250 CE, and in the Great Persecution early in the fourth century. When disaster struck, local Christians were sometimes accused of angering the gods, resulting in small scale mob attacks on Christian targets, but by and large it appears that Christianity prospered. Edward Gibbon (The Decline and Fall of the Roman Empire) believes the Christian tradition of widespread and savage official persecution began around the end of the fourth century, as justification for the persecution of the pagans by Christian authorities.
The Bible does not mention any Roman Emperor as persecuting the Church. In fact, there does not appear to have been any widespread, official persecution of the Church during the first century. The only exception to the first-century emperors ignoring or tolerating the Christians was when Emperor Nero blamed the Christians of Rome, probably unfairly, for starting the Great Fire of Rome. Edward Gibbon (The Decline and Fall of the Roman Empire) says that this did not extend to a general persecution of Christians throughout the empire.
325 AD.