the legal basis for official persecutions. There was, however, "no law, either existing section of criminal law, or special legislation directed against the Christians, under which Christians were prosecuted in the first two centuries." Rome lacked a uniform policy or legal code pertaining to foreign cults, and before Christian hegemony in the 4th century, there was no legal language to designate a concept analogous to "heresy" or crimes against orthodox religion. Some scholars have argued that Christianity was declared a religio illicita (an impermissible or illegitimate religion) by Nero following the Great Fire of Rome in 64. Under Constantine the Great, Christianity and other religions became tolerated with the Edict of Milan in 313. Toleration did not extend to religions that practiced human sacrifice, such as Druidism. This state of affairs lasted until 380, when Nicene Christianity was adopted as the state religion of the Roman Empire, after which time persecution of non-Christian and non-Nicene cults began. Priscillian was executed for heresy in 385, and Theodosius I began outlawing Rome's traditional religious rituals in 391. See also History of the Jews in the Roman Empire Persecution of the early Christians Religious toleration References Freedom of religion Roman law Ancient Roman religion 1st-century Christianity 4th-century Christianity Persecution of early Christians Christianity in the Roman Empire Jews and Judaism in the Roman Empire Religion in classical antiquity Jewish Italian history