(Caius Aurelius Valerius Diocletianus)


Diocletian is renowned, not only for bringing an end to the military anarchy of the Roman Empire, but for dividing the empire into western and eastern halves, and establishing an orderly succession, such that he was able to retire after a twenty year reign. Although the transition did not go as smoothly as he hoped, he died a natural death, only the second Roman emperor to do so in over one hundred years.

Christian martyrs
Diocletian was born of humble origins in the province of Illyria (modern day Croatia), and distinguished himself in the army under the reigns of Aurelian and Probus. He was proclaimed emperor by his troops in 284 A.D. after the murder of Numerian, and he faced the same threats of mutiny, and border invasions that had killed off so many of his predecessors. However, he applied himself to the problems of resisting Persian and Germanic incursions, and putting down internal uprisings with such energy, that in a few years he had secured fairly stable ascendency over the army. In 286 he appointed Maximian co-ruler in order to control the invasions on the German border, while he, himself, stayed mainly in the east. He was the first ruler to attempt to divide the empire into two separate regions and in 293 he officially named Maximian augustus of the West, and himself augustus of the East. At the same time he named two caesars, (Constantius I in the west, Galerius in the east) who would rule in conjunction with the augusti, and would assume power upon their death or retirement.

While Diocletian was still the active governor, the system worked fairly well. By 298 most of the border wars and internal uprisings had been suppressed, the administration of the empire was divided between the four rulers, and Diocletian could focus on internal reforms. He completely abandoned the last vestige of republican power still held by the Roman Senate, which by that time had degenerated into corrupt monopolies, and administered the empire as an absolute monarch. The empire by this time was troubled greatly by internal economic problems, including inflation, over-taxation, monopolies, and speculation. He attempted to address these problems with the Edict of Diocletian, which set maximum prices on a number of goods and wages, but, of course, this had limited success, and in some cases proved disastrous. The later years of his reign are also known for the most systematic and extensive persecutions of Christians that had occurred thus far, although this was done primarily under the direction of Galerius, his successor, rather than Diocletian himself.

After a vigorous and exhausting 20 year reign, Diocletian attempted to do what no other emperor had done before him: retire in peace. He insisted that Maximian step down at the same time as himself, and in 305 A.D., Constantius I, and Galerius were promoted to augusti. Unfortunately, the selection of new caesars did not go smoothly and before long the empire was again embroiled in a civil war, which eventually resulted in the elevation of Constantine. However, Diocletian deserves much credit for bringing to a close the crisis of the third century, which made the relatively successful reign of Constantine a possibility.

Key events during the life of Diocletian:

Proclaimed emperor on death of Numerian.
Became sole ruler after death of Carinus.
Appointed Maximian co-ruler in order to repel invasions on German border.
  Fought numerous wars to secure borders and put down uprisings.
Divided the empire, giving himself the east, and Maximian the west. Set up capitals outside of Rome.
Appointed Constantius I and Galerius caesars to effect orderly transition.
Britain was restored to the empire.
Persian and German borders were finally secured. Turned attention to government reforms.
Issued Edict of Diocletian, regulating prices and wages.
End of reign saw greatly increased persecution of Christians.
Retired peaceably from power, along with Maximian.
Constantine assumes assumes leadership of west and becomes embroiled in civil war.
Extensive and systematic persecution of Christians ends with death of Galerius.
Diocletian dies in retirement.

Other Resources

Story Links
Book Links
Prophecy Fulfulled  in  The Story of the Romans  by  H. A. Guerber
Diocletian  in  Back Matter  by  books/horne/soldiers/_back.html
Decline of the Roman Empire  in  The Discovery of New Worlds  by  M. B. Synge

Image Links

Army of Diocletian
 in Back Matter

Short Biography
Maximian Appointed augustus to co-rule with Diocletian.
Constantius I Father of Constantine; ruled briefly following retirement of Diocletian.
Galerius Ruled western empire following retirement of Diocletian.
Constantine First Christian emperor. Unified empire. Moved capital to Constantinople near Black Sea.
St. Helena Wife of Constantius Chlorus and mother of Constantine. Influenced her son to become Christian.