Christian life between Pliny's letter and the reign of Constantine was a constant stream of persecution, but the level of persecution through the ages fluctuated from the barely noticeable to the highly dangerous. Pliny's letter to the Emperor Trajan inquired about the empire's legal stance on Christians, how they were to be found, and what kind of punishment they should receive. Trajan's response told Pliny that Christians ought not to be sought out, but if their practices happened to be observed, then Christianity was punishable by death – meaning that the empire had adopted a sort of "don't ask, don't tell" policy regarding Christianity.
Later emperors, however, were not so relaxed in their persecutions. There were several emperors, such as the military-appointed Diocletian and the famously mad Nero, who actively sought out Christians and had them tortured and killed for their faith. Diocletian's persecution, which lasted from 303AD to 305AD, became known as the Great Persecution. But even in times of relative peace Christians had to live in a state of constant vigilance, because even when Christians were not actively being sought out for their faith, Christianity was still officially a crime. Christian persecution finally came to an end with the reign of the Emperor Constantine, who believed that he had been told in a dream to carry a cross, the symbol of Christianity, into battle. His victory on the battlefield convinced him that Christianity was the true religion, and his subsequent baptism put an end to the persecutions of Christians throughout the empire.