Emperor Diocletian issued the Edict on Maximum Prices, reforming the currency and setting price ceilings on a number of goods.

Emperor Galerius recognized Flavius Valerius Severus as Augustus in the west and granted Constantine the Great the lesser title of Caesar, which he accepted.

Emperor Constantine the Great ordered the death of his oldest son Crispus.

Emperor Constantine the Great campaigned against the Goths.

Emperor Constantine the Great campaigned against the Sarmatians.

Constantine II campaigned against the Alemanni.

Constantine II granted Illyria to his brother Constans.

Constans and Constantius II issued a ban against pagan sacrifice.

Emperor Constans was killed in Elne by followers of Usurper Magnentius.

Fleeing Hunnic aggression, the Goths, under the leadership of the Thervingi chieftain Fritigern, crossed the Danube and entered the eastern Empire as political refugees.

The capital of the Western Roman Empire was moved to Ravenna.

The Western Roman patrician Castinus declared the primicerius Joannes, Augustus.

Usurper Joannes was executed in Aquileia.

Attila abandoned his invasion of Italy following a meeting at the Mincio with the pope Pope Leo I.

General Ricimer's nephew Gundobad succeeded him as Magister Militum and took the title Patrician.

Patrician Gundobad relinquished his Western Roman titles to succeed his father as king of Burgundy.

Emperor Leo the Thracian appointed Julius Nepos, his nephew and governor of Dalmatia, ruler of the Western Roman Empire in opposition to Glycerius.

Emperor Nepos appointed Orestes (father of Romulus Augustulus) Magister Militum and commander-in-chief of the Western Roman military.

The Senate sent Eastern Roman Emperor Zeno the imperial regalia of the Western Roman Empire.

Constantius and Galerius were elevated to Augusti in the west and east.

Ex-Emperor Maximian resigned as augustus.

Emperor Diocletian died, possibly from suicide.

Emperors Constantine the Great and Licinius issued the Edict of Milan, providing for restitution to Christians injured during the persecutions.

Emperor Licinius recognized Emperor Constantine the Great as his superior, ceded all his territories outside of Thrace, and agreed to depose and execute Valerius Valens, whom he had raised to Augustus.

Emperor Constantine the Great moved his capital to Byzantium and renamed the city Constantinople, city of Constantine.

Emperor Constantine the Great's three sons declared themselves Augusti and divided their father's empire into three parts, with Constantine II (Emperor) receiving Britain, Iberia, Gaul and Illyria, Constantius II Asia, Syria Palaestina and Egypt, and Constans Italy and Africa.

Magnentius, commander of the Jovians and Herculians, was acclaimed ruler of Rome by his legions.

Emperor Constantius Chlorus's grandson Nepotianus entered Rome with a band of gladiators and there declared himself Imperator.

Marcellinus (Magister Officiorum), one of Usurper Magnentius's generals, entered Rome and executed Usurper Nepotianus.

Emperor Constantius II granted his cousin Constantius Gallus the title, Caesar.

Emperor Constantius II declared Julian, Caesar and granted him the command in Gaul.

Auxiliary force, The Petulantes, ordered east from Paris in preparation for a war with the Sasanian Empire, instead mutinied and proclaimed Julian Augustus.

Emperor Constantius II named Emperor Julian as his successor before dying of fever.

Deceased Emperor Julian's army declared one of their generals, Jovian, Augustus.

The army acclaimed the general Valentinian I, the Great Augustus.

Emperor Valentinian the Great appointed his younger brother Valens Augustus with rule over the eastern Empire, and continued as Augustus in the west.

Emperor Valentinian the Great died of a stroke.

The army acclaimed Valentinian the Great's young son Valentinian II, Augustus of the west.

Emperor Gratian named the general Theodosius I the Great, Augustus in the east.

Emperor Theodosius the Great issued the Edict of Thessalonica, making Christianity the state church of the Roman Empire.

Emperor Gratian was delivered by mutineers to the Magister equitum Andragathius and executed.

Emperor Valentinian II was found hanged in his residence.

Arbogast declared Eugenius, Augustus and ruler in the west.

Theodosius the Great appointed his younger son Honorius, Augustus in the west.

His elder son Arcadius succeeded him as Augustus in the eastern Byzantine Empire.

Emperor Honorius appointed his brother-in-law and Magister militum Constantius III co-ruler of the Western Roman Empire with himself.

The Byzantine Augustus Theodosius II The Younger, The Calligrapher named the young Valentinian III, his cousin and Constantius III's son, Caesar with rule over the west.

Emperor Theodosius the Younger died in a riding accident.

Emperor Valentinian III was assassinated on orders of the senator Petronius Maximus.

The Senate acclaimed Maximus Augustus of the Western Roman Empire.

Emperor Maximus was killed by a mob as he attempted to flee Rome in the face of a Vandal advance.

The Magister Militum Avitus was pronounced Augustus of the Western Roman Empire at Toulouse by the Visigothic king Theodoric II.

Emperor Avitus was forced to flee Rome following a military coup by the general Ricimer and the domesticus Majorian.

The Byzantine Augustus Leo I the Thracian appointed Majorian Magister Militum in the west.

The army acclaimed Majorian Augustus of the Western Roman Empire.

Emperor Majorian was killed after torture near the Staffora on general Ricimer's orders.

The Senate elected Libius Severus from among their number as Augustus of the Western Roman Empire.

Emperor Leo the Thracian elevated the 'comes' Anthemius to Caesar with rule over the Western Roman Empire.

Emperor Maximus's son Olybrius was acclaimed Augustus of the Western Roman Empire.

The Germanic elements of the army elected the domesticus Glycerius Augustus of the Western Roman Empire.

Zeno (Emperor) became co-Augustus of the Byzantine Empire with his young son Leo II.

Emperor Nepos deposed Emperor Glycerius.

Emperor Leo II died, possibly after being poisoned by his mother Ariadne (Empress).

Emperor Zeno was forced to flee Constantinople for his homeland Isauria in the face of a popular revolt.

Basiliscus, brother of Emperor Leo the Thracian's widow Verina, was acclaimed Augustus of the Byzantine Empire by the Byzantine Senate.

Emperor Orestes took control of the Western Roman capital Ravenna, forcing Emperor Nepos to flee to Dalmatia.

Emperor Orestes declared his young son Romulus Augustulus, Augustus of the Western Roman Empire.

Emperor Zeno recaptured Constantinople and accepted Emperor Basiliscus's surrender.

Germanic foederati under the command of the general Odoacer renounced Western Roman authority and declared Odoacer their king.

King Odoacer captured and executed Emperor Orestes at Piacenza.

Ex-Emperor Nepos was murdered in his residence in Split.

Emperor Diocletian issued his first edict against Christians, calling for the destruction of Christian holy books and places of worship and stripping Christians of their government positions and political rights.

Emperor Galerius appointed Flavius Valerius Severus Caesar in the west and Maximinus II Caesar in the east.

Emperors Diocletian and Maximian abdicated.

By Constantius's dying wish, his troops acclaimed his son Constantine the Great Augustus.

Emperor Maxentius invited Maximian to reclaim the title augustus.

Rioters in Rome acclaimed Maximian's son Maxentius ruler of Rome.

Emperor Maxentius took the title 'Princeps Invictus', undefeated prince.

Emperor Flavius Valerius Severus surrendered to Ex-Emperor Maximian at Ravenna.

Many of Emperor Galerius's soldiers defected to Emperor Maxentius and he was forced to flee.

After a failed coup against his son Emperor Maxentius, Ex-Emperor Maximian was forced to flee to Constantine's court.

Emperor Galerius appointed Licinius Augustus of the west and confirmed his recognition of Constantine the Great as Caesar of the west.

Ex-Emperor Maximian was forced to commit suicide following a failed coup against Constantine the Great.

Emperors Licinius and Maximinus agreed to divide the eastern Empire between themselves.

Emperor Constantine the Great concluded an alliance with Licinius, offering his half-sister Flavia Julia Constantia to him in marriage.

Emperor Maximinus entered a secret alliance with Maxentius.

Emperor Constantine the Great had a vision of the cross appearing over the sun at the Ponte Milvio with the words "In this sign, conquer."

Emperor Constatine the Great's forces defeated and killed Maxentius.

Emperor Licinius defeated a vastly numerically superior force loyal to Maximinus at modern Çorlu. Emperor Maximinus fled to Nicomedia.

Emperor Constantine the Great dealt a bloody defeat to Emperor Licinius's forces at modern Vinkovci.

After a bloody battle, probably at modern Harmanli, Emperor Licinius retreated from contact with Emperor Constantine the Great.

Emperor Licinius suffered a bloody defeat at the hands of Emperor Constantine the Great on the Maritsa.

Constantine the Great dealt a decisive defeat to the remnants of Licinius's army.

An ecumenical council called by Emperor Constantine the Great at Nicaea opened which would establish the Nicene Creed, asserting Jesus to be equal to and of the same substance as God the Father.

The Sasanian Shah Shapur II invaded Armenia and Mesopotamia.

The young Constans was placed under Constantine II's guardianship.

Constantine II was ambushed and slain at Aquileia by Constans, who inherited his territory.

Sasanian forces failed to capture the Roman fortress of Singara.

Emperor Constantius II defeated Usurper Magnentius in a bloody battle in the valley of the Drava.

Emperor Constantius II dealt Usurper Magnentius a decisive defeat at modern La Bâtie-Montsaléon.

Ceaser Julian defeated a vastly superior Alemanni force near Argentoratum, solidifying Roman control west of the Rhine.

Roman forces embarked from Antioch on a punitive expedition against the Sasanian Empire.

Sasanian forces harassed a Roman army in retreat at Samarra from a failed siege of their capital Ctesiphon.

Emperor Jovian agreed to cede the five provinces east of the Tigris to the Sasanian Empire, ending the war.

Deceased Emperor Valentinian The Great's son Gratian, then junior Augustus in the west, succeeded him as senior Augustus.

Following the deaths of several Roman soldiers during civil unrest in Thrace, the officer Lupicinus (Roman) arrested Gothic leaders, Thervingi chief Fritigern and the Greuthungi chieftain Alatheus.

A combined Gothic - Alanic force decisively defeated the Roman army near Edirne.

The Goths were made foederati of Rome and granted land and autonomy in Thrace, ending the war.

Emperor Valentinian II may have been murdered by his guardian, the Frankish general Arbogast.

Forces loyal to Emperor Theodosius the Great defeated and killed general Arbogast and Emperor Eugenius, probably near the Vipava.

The young Honorius became sole Augustus in the Western Roman Empire under the regency of Magister militum Stilicho.

Gildo, 'comes' (companion) of Africa, was killed following a failed rebellion against the Western Roman Empire.

A coalition of foreign tribes including the Vandals, Alans and Suebi invaded the Western Roman Empire across the Rhine.

Rome was sacked by the Visigoths under their king Alaric I.

Emperor Theodosius II the Younger's mother Galla Placidia was appointed regent.

The Huns under Attila defeated a Byzantine army in a bloody battle near the Vit.

The Vandals entered and began to sack Rome.

The Vandal Kingdom destroyed a combined Western Roman and Byzantine invasion fleet at Cap Bon.

Emperor Anthemius was killed in flight following general Ricimer's conquest of Rome.

Deceased Emperor Leo the Thracian was succeeded by his grandson Leo II.

King Odoacer conquered the Western Roman capital Ravenna, forced Emperor Romulus to abdicate and declared himself king of Italy.

The general Narses died.

The Lombards invaded Italy.

Justinian the Great ordered the construction of the Hagia Sophia in Constantinople.

Augustus Anastasius I Dicorus died.

Augustus Justin I appointed his older son Justinian I the Great co-Augustus with himself.

Emperor Justin I died.

The Codex Justinianeus, which attempted to consolidate and reconcile contradictions in Roman law, was promulgated.

The Hagia Sophia was completed.

General Belisarius dies.

Emperor Justinian the Great died.

Emperor Justin II died.

Emperor Augustus Tiberius II Constantine died.

A Byzantine force under the general Belisarius departed for the Vandal Kingdom.

A Byzantine army defeated a Vandal force near Carthage.

The Byzantines defeated a Vandal army and forced their king Gelimer into flight.

Gelimer surrendered to Belisarius and accepted his offer of a peaceful retirement in Galatia, ending the war.

The territory of the Vandal Kingdom was reorganized as the praetorian prefecture of Africa.

Byzantine forces crossing from Africa invaded Sicily, then an Ostrogothic possession.

Byzantium took Rome with little Ostrogothic resistance.

A Byzantine army dealt a decisive defeat to the Ostrogoths at Gualdo Tadino.

The Ostrogoth king Totila was killed.

An Ostrogothic force was ambushed and destroyed at Monti Lattari on its way to relieve a Byzantine siege of Cumae.

The Ostrogoth king Teia was killed.