In an attempt to resolve the difficulty and slowness of transmitting orders to the frontier, the new capitals of the Tetrarchic era were all much closer to the Empire's frontiers than Rome had been: Trier sat on the Rhine, Sirmium and Serdica were close to the Danube, Thessaloniki was on the route leading eastward, and Nicomedia and Antioch were important points in dealings with Persia.

The four Tetrarchic capitals were:

In the West, however, the loose ends of the Diocletianic settlement were about to bring the whole Tetrarchic tapestry down.

Both the Dyarchic and the Tetrarchic system ensured that an emperor was nearby to every crisis area to personally direct and remain in control of campaigns simultaneously on more than just one front.

Another important departure from Tetrarchic practice was the increase in the number of holders: no less than five prefects are attested for ca.

Coinage dating from the Tetrarchic period depicts every emperor with identical features — only the inscriptions on the coins indicate which one of the four emperors is being shown.

However, four full Augusti all at odds with each other did not bode well for the Tetrarchic system.

Although power was shared in the Tetrarchic system, the public image of the four emperors in the imperial college was carefully managed to give the appearance of a united empire ( patrimonium indivisum ).

Although effective while he ruled, Diocletian's Tetrarchic system collapsed after his abdication under the competing dynastic claims of Maxentius and Constantine, sons of Maximian and Constantius respectively.

This did not bode well for the future security of the Tetrarchic system.

He saw his Tetrarchic system fail, torn by the selfish ambitions of his successors.

Once he retired, however, his Tetrarchic system collapsed.

These centres are known as the Tetrarchic capitals.

However, it appears that some contemporary and later writers, such as the Christian author Lactantius, and Sextus Aurelius Victor ( who wrote about fifty years later and from uncertain sources ), misunderstood the Tetrarchic system in this respect, believing it to have involved a stricter division of territories between the four emperors.

The Tetrarchic system was at an end, although it took until 324 for Constantine to finally defeat Licinius, reunite the two halves of the Roman Empire and declare himself sole Augustus.

Although the Tetrarchic system as such only lasted until c. 313, many aspects survived.

Although Constantine was the son of the western emperor Constantius, the Tetrarchic ideology did not necessarily provide for hereditary succession.

Galerius ' death destabilized what remained of the Tetrarchic system.

They had been exempted from Decius's persecution and continued to enjoy freedom from persecution under Tetrarchic government.

Nevertheless, it remained one of the most splendid churches of the Eastern Empire, where the Byzantine Emperors were crowned.

Beneath the dome I saw the spot where the Byzantine Emperors were crowned, a bit of floor protected now by a wooden fence.

The Roman Emperors Constantius II ( 337 – 361 ) and Valens ( 364 – 378 ) were Arians or Semi-Arians.

Emperors Caracalla and Publius Septimius Geta, were his mother's maternal cousins.

He was a successor of Moctezuma and his brothers were Emperors Tizoc and Ahuitzotl and his sister was the Queen Chalchiuhnenetzin.

St Athanasius ' long episcopate lasted 45 years ( c. 8 June 328 – 2 May 373 ) of which over 17 years were spent in five exiles ordered by four different Roman Emperors, not counting approximately six more incidents in which he had to flee Alexandria for his own safety to escape people seeking to take his life.

Emperors were no longer peripatetic between various court capitals and palaces.

Imperial concubines, kept by Emperors in the Forbidden City, were traditionally guarded by eunuchs to ensure that they could not be impregnated by anyone but the Emperor.

The cities where Emperors lived frequently in this period — Milan, Trier, Arles, Sirmium, Serdica, Thessaloniki, Nicomedia, and Antioch — were treated as alternate imperial seats, to the exclusion of Rome and its senatorial elite.

Rescripts, authoritative interpretations issued by the Emperor in response to demands from disputants in both public and private cases, were a common duty of second-and third-century Emperors.

The Three Emperors ' League was discontinued, and Germany and Austria-Hungary were free to ally with one another against Russia.

There were no such dictatorships after the beginning of the 2nd century BC, and later dictators such as Sulla and the Roman Emperors exercised power much more personally and arbitrarily.

The first seven councils were called by the Byzantine Emperors and the sixteenth by the future Holy Roman Emperor Sigismund.

Emperors have been known to come into conflict with the reigning shogun from time to time ; a notable example is the Hōgen Rebellion of 1156, in which former Emperor Sutoku attempted to seize power from the then current Emperor Go-Shirakawa, both of whom were supported by different clans of samurai.

Emperors were once given precedence over kings in international diplomatic relations ; currently, precedence is decided by the length a head of state is continuously in office.

Few were however granted the title, and certainly not as a rule all wives of reigning Emperors.

In the late 3rd century, by the end of the epoch of the barracks emperors in Rome, there were two Britannic Emperors, reigning for about a decade.

After Junna stepped down from the throne, two former Emperors were alive.

Because of political necessity, the Holy Roman Emperors were restrained from directly naming bishops in the kingdom.

However, some magistrates – and some later Emperors – tacitly or openly condoned such transgressions and some volunteers were prepared to embrace the resulting loss of status.

Also all Roman Emperors before Hadrian, except for Nero ( also a great admirer of Greek culture ), were clean shaven.

Three members of the dynasty were crowned Holy Roman Emperors.

Charles V was the last to be a crowned Emperor ( elected 1519, crowned 1530 ); his successors were all Emperors by election (; ) only.

After Charles V, all individuals chosen by the electors were merely " Emperors elect ".