Theodosius I Biography


Birthday: January 11, 347 (Capricorn)

Born In: Coca, Segovia, Spain

Theodosius I, also known as Flavius Theodosius Augustus and Theodosius the Great, was the last ruler of the Roman Empire. Having gained military training under his father’s staff, he served in his father’s army. After his father’s humiliating death in 374, he stayed at his family estate for a brief period, away from all military and political activity. Later, in 378, Gratian, the emperor of the Western Roman Empire, restored him as the commander of the Eastern Roman Empire. After the death of Valens, the ruler of the Eastern Roman Empire, he was raised as the emperor of the Eastern Roman Empire, by default. He was baptized as a Nicean Christian in 380, and he declared the same as the state religion. Followers of other religions were persecuted. During his reign as the emperor of the eastern part of the Roman Empire, he continuously fought the invading Gothic tribes. However, he managed to strike an uneasy alliance with a few Gothic tribes and decimated others. The Roman Empire also faced two civil wars during his rule. Magnus Maximus killed Gratian to usurp the kingdom but was subdued by Theodosius. A few years later, Arbogast, who controlled Valentinian II, the successor of Gratian, was most likely the cause of the latter’s mysterious hanging. Arbogast then made an unsuccessful attempt to crown Eugenius as the emperor. Theodosius eliminated both of them and ruled the Roman Empire as the sole emperor until his death.
Quick Facts

Spanish Celebrities Born In January

Also Known As: Flavius Theodosius Augustus

Died At Age: 48


Spouse/Ex-: Aelia Flaccilla (m. ?–385 AD), Galla (m. ?–394 AD)

father: Theodosius the Elder

mother: Thermantia

children: Arcadius, Galla Placidia, Gratian, Honorius, Pulcheria

Born Country: Spain

Emperors & Kings Ancient Roman Men

Died on: January 17, 395

Childhood & Early Life
Theodosius was born on January 11, 347, to Theodosius the Elder and his wife, Thermantia. Not much is known about his place of birth. Some believe it was Cauca, while others believe it was Italica, both in present-day Spain.
His father served as a senior military officer for the Western Roman Empire.
He acquired military skills by training with his father’s men in Britannia (present-day Great Britain).
He was part of his father’s expedition to Britannia in 368 that brought an end to the conspiracy against the Roman Empire.
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Rise to the Throne
Around the year 373, he was chosen as the governor of Upper Moesia, and in a year, he became the military commander of the entire region of Moesia.
During his tenure in Moesia, he succeeded in keeping the Sarmatians and the Germanic tribes Alemanni and Quadi at bay.
However, after the twin deaths of his father and the ruler of the Western Roman Empire, Valentinian I, in 375, he retreated to his family residence in Gallaecia.
In 378, Gratian, one of the successors of Valentinian I and a co-ruler of the Western Roman Empire, rehabilitated Theodosius as the commander of the Illyrian army of the Eastern Roman Empire. The Eastern Roman Empire was then ruled by Valens, the brother of Valentinian I.
Between 378 and 380, he fought against the Goths. He lost the Battle of Adrianople. However, he reached an agreement with Athanaric, one of the most popular and influential leaders of the Gothic tribe Visigothic.
The death of Valens in 379 resulted in the automatic ascension of Theodosius to the throne of the Eastern Roman Empire.
Theodosius was baptized in 380. Later, he declared Nicean Christianity as the state religion by issuing the ‘Edict of Thessalonica’ (Thessalonica being the present-day Thessaloniki, Greece).
The ‘First Council of Constantinople’ was held in May 381, where Christian bishops from different regions gathered to settle the differences within the Church.
Under Theodosius, in 381, Christians began persecuting those who practiced Roman religions. Temples were destroyed, and rituals were banned. They also changed Roman religious days to working days, disbanded the order of the ‘Vestal Virgins,’ and probably discontinued the ‘Olympic Games’ in 393.
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The Ostrogothic branch of the Gothic tribe was not as fortunate as their counterparts and was defeated by Theodosius’s navy on the river Danube in 381 or 382.
On October 3, 382, the final peace treaty was signed with the remaining Gothic tribes, permitting them to blend in with the Roman citizens and become part of the imperial military.
When Gratian was killed by the usurper Magnus Maximus, who declared himself the king of the Western Roman Empire in 383, Theodosius kept the young Valentinian II safe from him. Five years later, in 388, Theodosius avenged the death of Gratian at the Battle of the Save, executing Maximus on August 28, 388. Valentinian II was made the ruler but was controlled by the general Arbogast.
In 390, Thessalonian Christians rebelled against the Gothic garrison in Thessalonica, and this led to the death of its commander. However, Gothics were allowed to kill thousands of Christians, as vengeance, by Theodosius.
As a result of his actions, Theodosius was excommunicated from the Church by St. Ambrose. However, after his repentance and penance, he was re-inducted to the Church.
Meanwhile, the uneasy arrangement between Valentinian II and Arbogast did not last long, as both of them had a public spat in 392.
Shortly, Valentinian was found hanging, and Arbogast tried to place his puppet, Eugenius, on the throne. However, Theodosius became the emperor of the whole empire. He foiled their plan and had Eugenius executed in September 394. Arbogast later committed suicide. Thus, Theodosius overcame all the opposition and ruled as the sole emperor of the Roman Empire until his death.
Family, Personal Life, & Death
Theodosius was initially married to Aelia Flaccilla Augusta, his first wife, who was probably of Spanish origin. They had two sons, Arcadius and Honorius, who co-ruled with their father, and a daughter, Aelia Pulcheria. In 385, he lost both Flaccilla and Pulcheria.
With his second wife, Galla, he had a son, Gratian, and a daughter, Aelia Galla Placidia. Gratian died at a young age. However, Aelia Galla lived longer to become an empress.
Theodosius died due to an illness on January 17, 395, and was buried in Constantinople on November 8, 395. Saint Ambrose delivered a eulogy titled ‘De Obitu Theodosii.’ His death spelled the decline of the empire. He was the last emperor to rule a united Roman Empire.

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