On This Day

Roman Emperor Theodosius I declares Christianity the state religion

Theodosius I (Ancient Greek: Θεοδόσιος Theodosios; 11 January 347 – 17 January 395), also known as Theodosius the Great, was Roman emperor from 379 to 395.

Theodosius I (Ancient Greek: Θεοδόσιος Theodosios; 11 January 347 – 17 January 395), also known as Theodosius the Great, was Roman emperor from 379 to 395. He won two civil wars and was instrumental in establishing the Nicene Creed as the orthodox doctrine for Nicene Christianity. Theodosius was the last emperor to rule the entire Roman Empire before its administration was permanently split between the Western Roman Empire and the Eastern Roman Empire.

Historical Significance

Theodosius I (Ancient Greek: Θεοδόσιος Theodosios; 11 January 347 – 17 January 395), also known as Theodosius the Great, was Roman emperor from 379 to 395.

Key People

Theodosius I

Roman emperor prior to the Splitting of Rome into East and West from 379 to 395

Roman emperor prior to the Splitting of Rome into East and West from 379 to 395

Events Before

  1. St Damasus I dies and ends his reign as Catholic Pope. Began reign 366

    Pope Damasus I (305 – 11 December 384), also known as Damasus of Rome, was the bishop of Rome from October 366 to his death in 384.

  2. Siricius, bishop of Tarragona, elected as Bishop of Rome; first to style himself Pope

    Siricius, bishop of Tarragona, elected as Bishop of Rome; first to style himself Pope

  3. Bishop Ambrose of Milan baptizes Augustine of Hippo

    Ambrose of Milan (Latin: Aurelius Ambrosius; c. 339 – 4 April 397), canonized as Saint Ambrose, was a theologian and statesman who served as Bishop of Milan from 374 to 397.

  4. Battle at Aquileja: Emperor Theodosius beats emperor Magnus Maximis

    Battle at Aquileja: Emperor Theodosius beats emperor Magnus Maximis

  5. BC Roman-Gaulish Wars: Battle of the Allia - Roman army is defeated by raiding Gauls, leads to subsequent sacking of Rom

    BC Roman-Gaulish Wars: Battle of the Allia - Roman army is defeated by raiding Gauls, leads to subsequent sacking of Rome

Events After

  1. BC Philosopher Socrates is sentenced to death by the city of Athens for corrupting the minds of the youth of the city an

    BC Philosopher Socrates is sentenced to death by the city of Athens for corrupting the minds of the youth of the city and for impiety

  2. Anastasius I begins his reign as Catholic Pope

    Anastasius I begins his reign as Catholic Pope

  3. St Anastasius I ends his reign as Catholic Pope

    Pope Anastasius I was the bishop of Rome from 27 November 399 to his death on 19 December 401. Anastasius was born in Rome, and was the son of Maximus.

  4. St. Innocent I begins his reign as Catholic Pope

    St. Innocent I begins his reign as Catholic Pope

More from the 390s

Frequently Asked Questions

What happened on November 8, 392?
Theodosius I (Ancient Greek: Θεοδόσιος Theodosios; 11 January 347 – 17 January 395), also known as Theodosius the Great, was Roman emperor from 379 to 395. He won two civil wars and was instrumental in establishing the Nicene Creed as the orthodox doctrine for Nicene Christianity. Theodosius was the last emperor to rule the entire Roman Empire before its administration was permanently split between the Western Roman Empire and the Eastern Roman Empire.
Why is Roman Emperor Theodosius I declares Christianity the state religion significant?
Theodosius I (Ancient Greek: Θεοδόσιος Theodosios; 11 January 347 – 17 January 395), also known as Theodosius the Great, was Roman emperor from 379 to 395.
Who was involved in Roman Emperor Theodosius I declares Christianity the state religion?
Key figures include Theodosius I (Roman emperor prior to the Splitting of Rome into East and West from 379 to 395).

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