nian II assumed the office of Emperor in the Western Roman Empire.
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. In the year 391, Valentinian II issued a law that not only prohibited sacrifices but also forbade anyone from visiting the temples. This again caused turbulence in the West. Valentinian II quickly followed this law with a second one, which declared that Pagan temples were to be closed, a law that was viewed as practically outlawing Paganism.
War on paganism by Theodosius (381-395)
The Christian persecution of paganism under Theodosius I began in 381, after the first couple of years his reign in the Eastern Roman Empire. In the 380s, Theodosius I reiterated Constantine's ban on Pagan sacrifice, prohibited haruspicy on pain of death, pioneered the criminalization of Magistrates who did not enforce anti-Pagan laws, broke up some pagan associations and destroyed Pagan temples.
Between 389-391 he emanated the infamous "Theodosian decrees," which established a practical ban on paganism; visits to the temples were forbidden, remaining Pagan holidays abolished, the eternal fire in the Temple of Vesta in the Roman Forum extinguished, the Vestal Virgins disbanded, auspices and witchcraft punished. Theodosian refused to restore the Altar of Victory in the Senate House when asked to do so by Pagan Senators.
In 392 he became emperor of the whole empire. From this moment till the end of his reign in 395, while Pagans remained outspoken in their demands for toleration, he authorized or participated in the killing of pagan priests, destruction of many temples, holy sites, images and objects of reverence throughout the empire and participated in actions by Christians against major Pagan sites. He likely suppressed the Ancient Olympic Games; the last record of the Olympics being celebrated in ancient Rome is from 393.
Persecution after Theodosius I till the Empire fall
Christian persecution of paganism after Theodosius I until the fall of the Roman Empire involved a long series of emperors, from both the Eastern and Western parts of the Empire, and ranged from 395 till 476.
Anti-Pagan laws were instated throughout this period, by emperors including Arcadius,  Honorius, Theodosius II, Marcian and Leo I the Thracian. The reiterations of the bans, especially on Pagan religious rites and sacrifices, and the increases in the penalties, indicated that the "Pagan" religion had still many followers. Significant support for Paganism was still present among Roman nobles, senators, magistrates, imperial palace officers, and other officials, who often protested or failed to enforce the edicts.
"Paganism" continued to be practiced by a large portion of the population, although the Pagans increasingly had to worship their gods undercover in order to comply formally with the edicts. There were many who pretended to convert to Christianity while secretly continuing Pagan practices, and many Christians converted back to Paganism; numerous laws against apostasy were promulgated and penalties increased from those in the time of Gratian and Theodosius. Pagans openly voiced their resentment in historical works, such as the writings of Eunapius and Olympiodorus; some writers blamed the Christian hegemony for the 410 Sack of Rome. Christians destroyed almost all such Pagan political literature, and threatened to cut off the hands of any copyist who dared to make new copies of the offending writings.
Laws declared that buildings belonging to known Pagans and heretics were to be appropriated by the churches. St. Augustine exhorted his congregation in Carthage to smash all tangible symbols of paganism they could lay their hands on. The persecution was somewhat reduced in some periods under the influence of the high-ranking general Stilicho and under the "usurper" Joannes Primicerius; a revival was attempted by Anthemius from 467.
After the Fall of the Roman Empire
Persecution by Eastern Emperor Zeno
Shortly thereaf