Answer
The Diocletianic Persecution, the last and most severe persecution of Christians in the Roman Empire, was brought to an end with the Edict of Toleration issued by Galerius in 311 AD. Galerius, one of the four emperors of the tetrarchy, recognized the futility of the persecutions and sought to restore stability to the empire. The edict granted freedom of worship to Christians and allowed them to rebuild their churches.