See study by N. Q. King (1960).
(born Jan. 11, 347, Cauca, Gallaecia [Spain]—died Jan. 17, 395, Mediolanum) Roman emperor of the East (379–392) and of East and West (392–395). Born of Christian parents, he served in the military under his father, a general. He distinguished himself against the Sarmatians and was proclaimed coemperor by Gratian to rule in the eastern empire (379). To settle the contentious debate over true Christianity, he adopted the Nicene Creed as the Christian norm (380). He reached a treaty with the Visigoths (382). When the Spanish general Maximus overthrew the new coemperor in the western empire (387), Theodosius defeated the usurper (388) and claimed supreme authority over the whole empire (392). He argued with St. Ambrose over the role of the church in imperial affairs but did not grant power to the church. In 392 forces advocating paganism led by Arbogast and Eugenius took power in Rome. In 394 Theodosius defeated them and claimed the Christian God victorious over the pagan gods.
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Flavius Theodosius (January 11, 347 – January 17, 395), also called Theodosius I and Theodosius the Great (Greek: Θεοδόσιος Α΄ and Θεοδόσιος ο Μέγας), was Roman Emperor from 379 to 395. Reuniting the eastern and western portions of the empire, Theodosius was the last emperor of both the Eastern and Western Roman Empire. After his death, the two parts split permanently. He is also known for making Nicene Christianity the official state religion of the Roman Empire.
The death of Valentinian I in 375 created political pandemonium. Fearing further persecution on account of his family ties, Theodosius abruptly retired to his family estates where he adapted to the life of a provincial aristocrat.
From 364 to 375, the Roman Empire was governed by two co-emperors, the brothers Valentinian I and Valens; when Valentinian died in 375, his sons, Valentinian II and Gratian, succeeded him as rulers of the Western Roman Empire. In 378, after Valens was killed in the Battle of Adrianople, Gratian appointed Theodosius to replace the fallen emperor as co-augustus for the East. Gratian was killed in a rebellion in 383, then Theodosius appointed his elder son, Arcadius, his co-ruler for the East. After the death in 392 of Valentinian II, whom Theodosius had supported against a variety of usurpations, Theodosius ruled as sole emperor, appointing his younger son Honorius Augustus and his co-ruler for the West (Milan, on January 23, 393) and defeating the usurper Eugenius on September 6, 394, at the Battle of the Frigidus (Vipava river, modern Slovenia) he restored peace.
His second wife (but never declared Augusta) was Galla, daughter of the emperor Valentinian I and his second wife Justina. Theodosius and Galla had three children who were a son, Gratian, born in 388 who died young and a daughter Aelia Galla Placidia (392–450). Placidia was the only child who survived to adulthood and later become an Empress; a third child (a son), John, died with his mother in childbirth in 394.
The Goths and their allies (Vandali, Taifalae, Bastarnae and the native Carpi) entrenched in the provinces of Dacia and eastern Pannonia Inferior consumed Theodosious' attention. The Gothic crisis was so dire that his co-Emperor Gratian relinquished control of the Illyrian provinces and retired to Trier in Gaul to let Theodosius operate without hindrance. A major weakness in the Roman position after the defeat at Adrianople was the recruiting of barbarians to fight against other barbarians. In order to reconstruct the Roman Army of the West, Theodosius needed to find able bodied soldiers and so he turned to the most capable men readily to hand: the barbarians recently settled in the Empire. This caused many difficulties in the battle against barbarians since the newly recruited fighters had little or no loyalty to Theodosius.
Theodosius was reduced to the costly expedient of shipping his recruits to Egypt and replacing them with more seasoned Romans, but there were still switches of allegiance that resulted in military setbacks. Gratian sent generals to clear the dioceses of Illyria (Pannonia and Dalmatia) of Goths, and Theodosius was able finally to enter Constantinople on November 24, 380, after two seasons in the field. The final treaties with the remaining Gothic forces, signed October 3, 382, permitted large contingents of primarily Thervingian Goths to settle along the southern Danube frontier in the province of Thrace and largely govern themselves.
The Goths now settled within the Empire had, as a result of the treaties, military obligations to fight for the Romans as a national contingent, as opposed to being fully integrated into the Roman forces. However, many Goths would serve in Roman legions and others, as foederati, for a single campaign, while bands of Goths switching loyalties became a destabilizing factor in the internal struggles for control of the Empire. In the last years of Theodosius' reign, one of their emerging leaders named Alaric, participated in Theodosius' campaign against Eugenius in 394, only to resume his rebellious behavior against Theodosius' son and eastern successor, Arcadius, shortly after Theodosius' death.
After the death of Gratian in 383, Theodosius' interests turned to the Western Roman Empire, for the usurper Magnus Maximus had taken all the provinces of the West except for Italy. This self-proclaimed threat was hostile to Theodosius' interests, since the reigning emperor Valentinian II, Maximus' enemy, was his ally. Theodosius, however, was unable to do much about Maximus due to his still inadequate military capability and he was forced to keep his attention on local matters. However when Maximus began an invasion of Italy in 387, Theodosius was forced to take action. The armies of Theodosius and Maximus met in 388 at Poetovio and Maximus was defeated. On August 28, 388 Maximus was executed.
Trouble arose again, after Valentinian was found hanging in his room. It was claimed to be a suicide by the magister militum, Arbogast. Arbogast, unable to assume the role of emperor, elected Eugenius, a former teacher of rhetoric. Eugenius started a program of restoration of the Pagan faith, and sought, in vain, Theodosius' recognition. In January of 393, Theodosius gave his son Honorius the full rank of Augustus in the West, citing Eugenius' illegitimacy.
Theodosius campaigned against Eugenius. The two armies faced at the Battle of Frigidus in September of 394. The battle began on September 5, 394 with Theodosius' full frontal assault on Eugenius' forces. Theodosius was repulsed and Eugenius thought the battle to be all but over. In Theodosius' camp the loss of the day decreased morale. It is said that Theodosius was visited by two "heavenly riders all in white" who gave him courage. The next day, the battle began again and Theodosius' forces were aided by a natural phenomenon known as the Bora, which produces cyclonic winds. The Bora blew directly against the forces of Eugenius and disrupted the line.
Eugenius' camp was stormed and Eugenius was captured and soon after executed. Thus Theodosius became the only emperor.
Theodosius oversaw the removal in 390 of an Egyptian obelisk from Alexandria to Constantinople. It is now known as the obelisk of Theodosius and still stands in the Hippodrome, the long racetrack that was the center of Constantinople's public life and scene of political turmoil. Re-erecting the monolith was a challenge for the technology that had been honed in the construction of siege engines. The obelisk, still recognizably a solar symbol, had been moved from Karnak to Alexandria with what is now the Lateran obelisk by Constantius II). The Lateran obelisk was shipped to Rome soon afterwards, but the other one then spent a generation lying at the docks due to the difficulty involved in attempting to ship it to Constantinople. Eventually, the obelisk was cracked in transit. The white marble base is entirely covered with bas-reliefs documenting the Imperial household and the engineering feat of removing it to Constantinople. Theodosius and the imperial family are separated from the nobles among the spectators in the Imperial box with a cover over them as a mark of their status. The naturalism of traditional Roman art in such scenes gave way in these reliefs to conceptual art: the idea of order, decorum and respective ranking, expressed in serried ranks of faces. This is seen as evidence of formal themes beginning to oust the transitory details of mundane life, celebrated in Pagan portraiture. Christianity had only just been adopted as the new state religion.
The Emperor Valens had favored the group who used the homoios formula; this theology was prominent in much of the East and had under the sons of Constantine the Great gained a foothold in the West. Theodosius, on the other hand, cleaved closely to the Nicene Creed which was the interpretation that predominated in the West and was held by the important Alexandrian church.
On February 27, 380 he, Gratian and Valentinian I published an edict in order that all their subjects should profess the faith of the bishops of Rome and Alexandria (i.e., the Nicene faith). The move was mainly a thrust at the various beliefs that had arisen out of Arianism, but smaller dissident sects, such as the Macedonians, were also prohibited. The exact text of this decree, gathered in the Codex Theodosianus XVI.1.2, was:
It is our desire that all the various nations which are subject to our Clemency and Moderation, should continue to the profession of that religion which was delivered to the Romans by the divine Apostle Peter, as it has been preserved by faithful tradition and which is now professed by the Pontiff Damasus and by Peter, Bishop of Alexandria, a man of apostolic holiness. According to the apostolic teaching and the doctrine of the Gospel, let us believe the one deity of the Father, the Son and the Holy Spirit, in equal majesty and in a holy Trinity. We authorize the followers of this law to assume the title of Catholic Christians; but as for the others, since, in our judgment they are foolish madmen, we decree that they shall be branded with the ignominious name of heretics, and shall not presume to give to their conventicles the name of churches. They will suffer in the first place the chastisement of the divine condemnation and in the second the punishment of our authority which in accordance with the will of Heaven shall decide to inflict.
In May 381, Theodosius summoned a new ecumenical council at Constantinople to repair the schism between East and West on the basis of Nicean orthodoxy. "The council went on to define orthodoxy, including the mysterious Third Person of the Trinity, the Holy Ghost who, though equal to the Father, 'proceeded' from Him, whereas the Son was 'begotten' of Him." The council also "condemned the Apollonian and Macedonian heresies, clarified church jurisdictions according to the civil boundaries of dioceses and ruled that Constantinople was second in precedence to Rome."
With the death of Valens, the Arians' protector, his defeat probably damaged the standing of the Homoian faction.
Valentinian II's death sparked a civil war between Eugenius and Theodosius over the rulership of the west in the Battle of the Frigidus. The resultant eastern victory there led to the final brief unification of the Roman Empire under Theodosius, and the ultimate irreparable division of the empire after his death.
In 388 he sent a prefect to Syria, Egypt, and Asia Minor with the aim of breaking up pagan associations and the destruction of their temples. The Serapeum at Alexandria was destroyed during this campaign. In a series of decrees called the "Theodosian decrees" he progressively declared that those Pagan feasts that had not yet been rendered Christian ones were now to be workdays (in 389). In 391, he reiterated the ban of blood sacrifice and decreed "no one is to go to the sanctuaries, walk through the temples, or raise his eyes to statues created by the labor of man. The temples that were thus closed could be declared "abandoned", as Bishop Theophilus of Alexandria immediately noted in applying for permission to demolish a site and cover it with a Christian church, an act that must have received general sanction, for mithraea forming crypts of churches, and temples forming the foundations of 5th century churches appear throughout the former Roman Empire. Theodosius participated in actions by Christians against major Pagan sites: the destruction of the gigantic Serapeum of Alexandria by soldiers and local Christian citizens in 392, according to the Christian sources authorized by Theodosius (extirpium malum), needs to be seen against a complicated background of less spectacular violence in the city: (That a large library was resident in the Serapeum, however, which was destroyed along with the temple, is a modern tale, generated by a single sentence in Gibbon; no ancient evidence supports it, and even pagan sources show it to be false: Ammianus, for instance, indicates that the Serapeum library was no longer in existence in 392, and Eunapius of Sardis's angry account of the demolition seems to make it clear that no library was destroyed.) Eusebius mentions street-fighting in Alexandria between Christians and non-Christians as early as 249, and non-Christians had participated in the struggles for and against Athanasius in 341 and 356. "In 363 they killed Bishop George for repeated acts of pointed outrage, insult, and pillage of the most sacred treasures of the city.
By decree in 391, Theodosius ended the subsidies that had still trickled to some remnants of Greco-Roman civic Paganism too. The eternal fire in the Temple of Vesta in the Roman Forum was extinguished, and the Vestal Virgins were disbanded. Taking the auspices and practicing witchcraft were to be punished. Pagan members of the Senate in Rome appealed to him to restore the Altar of Victory in the Senate House; he refused. After the last Olympic Games in 393, it is believed that Theodosius cancelled the games although there is no proof of that in the official records of the Roman Empire, and the reckoning of dates by Olympiads soon came to an end. Now Theodosius portrayed himself on his coins holding the labarum.
The apparent change of policy that resulted in the "Theodosian decrees" has often been credited to the increased influence of Ambrose, bishop of Milan. It is worth noting that in 390 Ambrose had excommunicated Theodosius, who had recently ordered the massacre of 7,000 inhabitants of Thessalonica, in response to the assassination of his military governor stationed in the city, and that Theodosius performed several months of public penance. The specifics of the decrees were superficially limited in scope, specific measures in response to various petitions from Christians throughout his administration.
Some modern historians question the consequences of the laws against pagans.