Tetrarchy

In 285, Emperor Diocletian appointed military commander Maximian the younger co-ruler ( “Caesar” ), and in 286 - “August” . Diocletian ruled the eastern half of the empire, and Maximian controlled the western half. In the year 293 , considering that military and civilian problems required specialization, Diocletian, with the consent of Maximian, appointed two Caesars as august augusts: Galeria and Constance Chlorus . It was assumed that the Augustans would abdicate after a 20-year reign, and the power would pass to the Caesars. So the first tetrarchy was created.

The four tetrarchs were not based in Rome , but in other cities closer to the borders - military headquarters, guiding the defense of the empire from enemies ( Sassanian Persia ) and barbarians (mainly Germans , as well as numerous nomads from the eastern steppes) on the Rhine and Danube . These cities are known as the "capital of the tetrarchs." Although Rome ceased to be the current capital, the Eternal City remained the nominal capital of the entire empire. He was not reduced to the provincial level, but was subject to the prefect of the city (praefectus urbis). Subsequently, the same system was introduced in Constantinople .

The four capitals of the tetrarchs were:

• Nicomedia in northwestern Asia Minor (now Izmit in Turkey ), a base for protection against invasions from the Balkans and from Persia . Nicomedia was the capital of Diocletian, eastern and most important August. During the last reorganization in 318 by Constantine I the Great, its area, adjacent to the most powerful enemy - Persia, became the Praetorian prefecture Oriens ("East"), the core of the future Byzantium .

• Sirmy (now Sremska Mitrovica in the Vojvodina region of modern Serbia , near Belgrade ) on the Danube border was the capital of Galeria, eastern Caesar. It became the Balkan-Danube prefecture of Illyria .

• Mediolanus (now Milan , near the Alps ), and not Rome, was the capital of Maximian, western August. Italy and Africa, with a small extent of external borders, became its region.

• Augusta Treverorum (now Trier , in Germany ) was the distant capital of Constance Chlorus, western Caesar, near the important border of the Rhine . Therefore, a little earlier, it was the capital of the Gallic emperor Tetric I. This quarter became the prefecture of Gaul and included Germany, Gaul, Spain and Britain.

Aquileia , a port on the Adriatic coast, and Eborac (now York ) in northern England, near the Celtic tribes in modern Scotland and Ireland ) were also important cities for Maximian and Constance, respectively.

There was no clear division of land between the four tetrarchs, so it cannot be assumed that at that time the Roman Empire split into four states. Each emperor had a zone of influence within the Roman Empire, but nothing more. The supreme power actually belonged to Diocletian. Basically, everyone was involved in the command of military campaigns, and the bureaucracy headed by the prefect of the pretoria of each tetrarch was in charge. The vicars , who headed the dioceses , administrative units, which at first were twelve, and later fifteen, were subordinate to the prefects . The diocese included up to 16 provinces .

See the list of Roman provinces .

In the west of August, Maximian ruled the provinces west of the Adriatic and Small Sirte , and inside this region his Caesar, Constantius, controlled Gaul, Britain, Germany and Spain. In the east, the relationship between Augustus Diocletian and his Caesar Gallery was delineated much less clearly.

Riots and fall

In 305, the 20-year term of Diocletian and Maximian ended, and both resigned. Their Caesars, Galerius and Constantius Chlorus, both became Augustus and appointed two new Caesars, Maximinus - Gallery and Flavius ​​Valerius Severus - Constantius. The four of them formed the second tetrarchy.

However, this system was soon disrupted. When Constantius died in 306 , Galerius appointed Severus as Augustus, while Constantine I , son of Constantius, was also proclaimed Augustus by the troops of his father. At the same time, Maxentius , the son of Maximianus, did not want to be expelled and defeated the North, forcing him to renounce the throne. Then Maxentius ordered the assassination of the North in 307. Both Maxentius and Maximian proclaimed themselves Augustans. Thus, in 308 , four applicants were formed for the title of August (Galerius, Konstantin, Maximian and Maxentius), and only one for the rank of Caesar (Maximin).

In 308 , Galerius, together with the retired Diocletian and, apparently, retired Maximian, convened an imperial conference in Karnuntum on the Danube, where it was decided that Licinius would become August in the west, and Constantine his Caesar. In the east, Augustus will remain Galerius, and Maximin will remain his Caesar. Maximian had to retire, and Maxentius was declared a usurper. This agreement did not lead to anything good - by 308 , Maxentius, deprived of the imperial throne, still became the de facto ruler of Italy and Africa . In addition, neither Konstantin nor Maximin — both Caesars since 305 — were prepared to endure Licinius' appointment to the post of August.

They tried to calm Konstantin and Maximin by granting them the meaningless title filius Augusti ("son of Augustus", which was no different from the rank of Caesar, because it also implied inheritance), but in 309 they were also recognized as Augustans. However, the existence of four equal Augustes, quarreling with each other, did not bode well.

The End of the Tetrarchy

Between 309 and 313 , most applicants for imperial posts died or were killed in internal strife. Constantine ordered the strangulation of Maximian in 310. Galerius died of natural causes in 311. Constantine defeated Maxentius at the Battle of Milvi Bridge in 312 , and Maxentius was soon killed. Maximin committed suicide in Tarsus in 313 , having been defeated by Licinius.

By 313, only two emperors remained: Constantine in the west and Licinius in the east. The tetrarchy was completed, although it was only in 324 that Constantine defeated Licinius, united both halves of the Roman Empire, and proclaimed himself the only August.

Although the tetrarchy lasted only until 313 years , many of its features have survived subsequently. The division of the empire into four regions continued in the form of prefectures , each of which was governed by the praetorian prefect . The prefectures were divided into dioceses , which in turn were divided into provinces .

The concept of consortium imperii , the separation of imperial power, repeatedly appeared in the future.

The idea of ​​dividing into two parts, west and east, also did not disappear. In the end, it led to the division into two independent Roman empires.

Ancient Thessaly was divided into tetrarchies: these were Thessaliotis, Fthiotides, Pelazgiotides and Histieotides. Philip II of Macedon during the reorganization of Thessaly restored the original division of the region into four districts, and along with the tetrarchy established the so-called decarchies .

Tetrarchies were also called parts of the regions occupied in Galatia (in Asia Minor) by three Gallic tribes ( trocms , tectosagi and toliboids ): each part was headed by a tetrarch , who had the highest military and judicial power, which was hereditary and lifelong.

Twelve tetrarchs and 300 elders made up the national assembly of the three tribes. This division of Galatia into tetrarchies was maintained until the time of Pompey, in which the whole area was united under the rule of one ruler, Deiotar .

The rulers of some Syrian tribes and some of the members of the reigning house of Herodias in Palestine were also known under the name of the tetrarchs .

• Barnes, Timothy D. The New Empire of Diocletian and Constantine . Cambridge, MA: Harvard University Press, 1982. ISBN 0-7837-2221-4