The persecution of pagans under Theodosius I began in 381, after the first couple of years of his reign as co-emperor in the eastern part of the Roman Empire.
Between 389 and 391 he issued the "Theodosian decrees", which established a practical ban on paganism;[1] visits to the temples were forbidden, the remaining pagan holidays were abolished, the sacred fire in the Temple of Vesta in the Roman Forum was extinguished as the Vestal Virgins were disbanded, and auspices and witchcraft were deemed punishable offenses.
From this moment until the end of his reign in 395, while pagans remained outspoken in their demands for toleration,[2][3] he authorized or participated in the destruction of many temples, holy sites, images and objects of piety throughout the empire[4][5][6][page needed][7][page needed][8] in actions by Christians against major pagan sites.
[15] Theodosius I's relative tolerance for other religions is also indicated by his later order (in 388) for the reconstruction of a Jewish synagogue at Callinicum in Mesopotamia, which had been destroyed by a bishop and his Christian flock.
Even though deprived of State and municipal support, bereft of funds and property the followers of the old religions continued to survive visibly, though under pressure and weakening, into the early 6th century.
In 388 Theodosius sent a prefect to Syria, Egypt, and Asia Minor with the aim of breaking up pagan associations and the destruction of their temples.
Also in 391, Valentinian II, who was emperor in the West under the aegis of Theodosius, was advised by Ambrose to issue a law that not only prohibited sacrifices but also forbade anyone from visiting the temples.
Valentinian II, advised by Ambrose, and in spite of pleas from the pagans, refused to restore the Altar of Victory to the Senate House, or their income to the priests and Vestal Virgins.
The apparent change of policy that resulted in the "Theodosian decrees" has often been credited to the increased influence of Ambrose, bishop of Milan.
An individual's punishment for sacrificing in temples or shrines was a fine of twenty-five pounds of gold[30] In 391 in Alexandria in the wake of the great anti-pagan riots "busts of Serapis which stood in the walls, vestibules, doorways and windows of every house were all torn out and annihilated..., and in their place the sign of the Lord's cross was painted in the doorways, vestibules, windows and walls, and on pillars.
"In 363 they killed Bishop George for repeated acts of pointed outrage, insult, and pillage of the most sacred treasures of the city.
"[9] In 391 riots broke out between supporters of Theodosius's Imperial Prefect and the supporters of the independent Patriarch of Alexandria as to who really governed in Alexandria; the rioters opposing the patriarch took refuge in the Serapeum and used it as a fortress; when order was restored the prefect ordered it demolished so future rioters could not use it for the same purpose.
[10][32] Theodosius prohibited imperial palace officers and magistrates from honoring their Lares with fire, their Genius with wine, or their Penates with incense.
[7] The leader of the Egyptian monks who participated in the sack of temples replied to the victims who demanded back their sacred icons: "I peacefully removed your gods... there is no such thing as robbery for those who truly possess Christ.
"[10][33] Edward Gibbon writes: "The generation that arose in the world after the promulgation of the Imperial laws was attracted within the pale of the Catholic Church: and so rapid, yet so gentle, was the fall of paganism that only twenty-eight years after the death of Theodosius the faint and minute vestiges were no longer visible to the eye of the legislator.