Gregory was eventually called forth from his pit in c. 297 to restore to sanity Tiridates III, who had lost all reason after he was betrayed by Roman emperor Diocletian.

Aside from the rank and file legionary ( who received the base wage of 10 asses a day or 225 denarii a year ), the following list describes the system of officers which developed within the legions from the Marian reforms ( 104 BC ) until the military reforms of Diocletian ( c. 290 ).

Saint George ( c. 275 / 281 – 23 April 303 ) was, according to tradition, a Roman soldier from Syria Palaestina and a soldier in the Guard of Diocletian, who is venerated as a Christian martyr.

The six Scriptores – " Aelius Spartianus ", " Iulius Capitolinus ", " Vulcacius Gallicanus ", " Aelius Lampridius ", " Trebellius Pollio ", and " Flavius Vopiscus ( of Syracuse )" – dedicate their biographies to Diocletian, Constantine and various private persons, and so ostensibly were all writing c. the late third and early fourth century.

Restitution of Emperor Diocletian Palace in Split ( city ) | Split, c. 300 AD

The tetrarchy reform of Diocletian ( c. 296 ) multiplied the office, there was a praetorian prefect as chief of staff ( military and administrative )— rather than commander of the guard — for each of two Augusti, but not for the two Caesars.

Arnobius of Sicca ( died c. 330 ) was an Early Christian apologist, during the reign of Diocletian ( 284 – 305 ).

Numbers were restored to their early 2nd-century level of c. 400, 000 ( but probably not to their 211 peak ) under Diocletian ( r. 284 – 305 ).

With the benefit of archaeological discoveries of recent decades, many contemporary historians view the late army as no larger than its predecessor: under Diocletian c. 390, 000 ( the same as under Hadrian almost 2 centuries earlier ) and under Constantine no greater, and probably somewhat smaller, than the Principate peak of c. 440, 000.

Building took place between the year it was first commissioned and was finished sometime between the abdication of Diocletian in 305 c. e.

Britannia Secunda was one of the provinces of Roman Britain in existence by c. 312 AD and probably created as part of the administrative reforms of the Roman Emperor Diocletian after the defeat of the usurper Allectus by Constantius Chlorus in 296 AD.

After the Crisis of the Third Century almost resulted in the Roman Empire's political collapse, the Emperor Diocletian replaced the one-headed Principate with the tetrarchy ( c. 300 AD, two Augusti ranking above two Caesares ), in which the remaining pretense of the old Republican forms was largely abandoned.

* 286 – Emperor Diocletian elevates his general Maximian to co-emperor with the rank of Augustus and gives him control over the Western regions of the Roman Empire.

Alexander ’ s reign contained some of the last major building works constructed in Rome before the reign of Diocletian.

Although the Principate continued in theory until the reign of Diocletian, Severus Alexander's death signalled the beginning of the chaotic period known as the Crisis of the Third Century which brought the empire to near collapse.

In his Easter table the year 532 AD was equated with the regnal year 248 of Emperor Diocletian.

Ar., lxiv, and De Syn., xviii ), St Athanasius does not recall from memory being a first hand witness to the onset of the great persecution by the Tetrarchy of Diocletian and Maximian in February 303, for in referring to the events of this period he makes no direct appeal to his own personal recollections, but falls back on tradition.

The most usual shabi term for the geographic area of a bishop's authority and ministry, the diocese, began as part of the structure of the Roman Empire under Diocletian.

A further massive transfer of Bastarnae was carried out by emperor Diocletian ( ruled 284-305 ) after he and his colleague Galerius defeated a coalition of Bastarnae and Carpi in 299.

Such numbers may have amounted to a substantial proportion, if not all, of the Peucini Bastarnae: Victor claims that the Carpi resettled in Pannonia by Diocletian at the same time, together with those previously transferred by Aurelian, amounted to the entire Carpi tribe.

Art dating from the Diocletian period ( 286 – 305 AD ) in Villa Romana del Casale, Sicily depicts women in garments resembling bikinis in mosaics on the floor.

Palace of the Roman Emperor Diocletian, around which the Croatian city of Split ( city ) | Split emerged.

Dalmatia was the birthplace of the Roman Emperor Diocletian, who, upon retirement from Emperor in AD 305, built a large palace near Salona, out of which the city of Split later developed.

After the Western Roman Empire collapsed in 476, with the beginning of the Migration Period, Julius Nepos shortly ruled his diminished domain from the Diocletian palace after his 476 flight from Italy.

Also, alone in Europe until the 13th century Italian florin, the Empire continued to produce sound gold coinage, the solidus of Diocletian becoming the bezant prized throughout the Middle Ages.

Born to a family of low status in the Roman province of Dalmatia, Diocletian rose through the ranks of the military to become cavalry commander to the Emperor Carus.

After the deaths of Carus and his son Numerian on campaign in Persia, Diocletian was proclaimed Emperor.

The title was also claimed by Carus ' other surviving son, Carinus, but Diocletian defeated him in the Battle of the Margus.

Diocletian delegated further on 1 March 293, appointing Galerius and Constantius as Caesars, junior co-emperors.

Diocletian secured the Empire's borders and purged it of all threats to his power.

Galerius, aided by Diocletian, campaigned successfully against Sassanid Persia, the Empire's traditional enemy.

Diocletian led the subsequent negotiations and achieved a lasting and favorable peace.

Diocletian separated and enlarged the Empire's civil and military services and reorganized the Empire's provincial divisions, establishing the largest and most bureaucratic government in the history of the Empire.

Weakened by illness, Diocletian left the imperial office on 1 May 305, and became the only Roman emperor to voluntarily abdicate the position.

Diocletian was probably born near Salona in Dalmatia ( Solin in modern Croatia ), some time around 244.

Since 22 BC it was a senatorial province, after the reforms of Diocletian it was placed under the Consularis Oriens.

Diocletian met Maximian in Milan in the winter of 290 – 91, either in late December 290 or January 291.

Domitianus died in December 297, by which time Diocletian had secured control of the Egyptian countryside.

On 20 December 303, Diocletian cut short his stay in Rome and left for the north.

* 244 – Diocletian, Roman Emperor ( d. 311 )

* Diocletian ( 244 – 311 ), Roman emperor formerly named Diocles

It was organized into Moesia, later Moesia Superior, and in the administrative reforms of Diocletian ( 244 – 311 ) it was part of the Diocese of Moesia, then the Diocese of Dacia.