Diocletian

Roman emperor who stabilized the empire, initiated the Tetrarchy, and abdicated voluntarily.

His accession on 20 November 284 is said to mark the end of the third-century crisis and to usher in a period of recovery and major reform.^[1] He inaugurated the tetrarchy system of government in 293, sharing control of the empire between four rulers.^[1] Diocletian's birthplace was Dalmatia, likely in or near the town of Salona (modern Solin, Croatia), and he was originally named Diocles (full name Gaius Valerius Diocles), a name possibly derived from his mother Dioclea and her supposed birthplace.^[2]

Quick Facts

Reign: 20 November 284 – 1 April 286, 1 April 286 – 1 May 305 (East)
Predecessor: Carinus
Successor: Galerius (East), Constantius I (West)
Regent: Maximian (in the West)
Birth name: Diocles
Birthplace: Salona, Dalmatia, Roman Empire
Died: 3 December 311/312 (aged c. 68)
Place of death: Aspalathos, Dalmatia, Roman Empire

Facts from the source article.

Life and work

His parents were of low status, with Eutropius recording that most writers said he was the son of a scribe.^[3] He served as commander of the Protectores domestici under Emperor Carus in 282, which earned him a consulship in 283.^[4] Diocletian raised Maximian to the rank of Caesar, and Maximian took charge in the West while Diocletian returned to the East.^[1] Diocletian remained the senior partner, assuming the title Jovius, while Maximian took that of Herculius.^[1]

According to estimates based on a statement that he died at age 68, Diocletian's birth year falls between 242 and 245, and his official birthday is recorded as 22 December.^[3] Before the assembled troops, Diocles drew his sword, killed Aper, and swore an oath while raising his blade to the sun that he bore no responsibility for Numerian's death, claiming that Aper had murdered Numerian and concealed the crime.^[5]

What the cited sources add

Stephen J. Murray's account notes that Diocletian's accession ended the half-century-long third-century crisis and began a period of recovery lasting until Constantine's death in 337.^[1] The same source states that Carinus had ruled in the West while Numerian ruled in the East before Diocletian's rise.^[1] Murray reports that Diocletian quickly raised Maximian to Caesar, with Maximian taking charge in the West.^[1] The tetrarchy system inaugurated in 293 involved each Augustus elevating a subordinate to Caesar, with Galerius serving Diocletian and Constantius serving Maximian.^[1]

Under Diocletian's reformed system, the diocese of the Britains comprised four provinces: Britannia Prima, Britannia Secunda, Flavia Caesariensis, and Maxima Caesariensis.^[1]

References

Stephen J. Murray, "New Empires", From Dot To Domesday – British History, 2021. facts only, no text reused. dot-domesday.me.uk
Wikipedia, "Diocletian" (CC BY-SA 4.0), which cites: Cambi, "Diokletian und die Tetrarchie", De Gruyter, 2012, p. 38–45 (we also read that source) en.wikipedia.org
Wikipedia, "Diocletian" (CC BY-SA 4.0), which cites: Wilkes, "The Illyrians", Blackwell Publishing, 1992, p. 263; Wilkes, "The Illyrians", Blackwell Publishing, 1992, p. 263; Odahl 2004, p. 36-40; Odahl 2004, p. 36-40; Barnes 1982, p. 4; Williams 1985, p. 26 (we also read that source) en.wikipedia.org
Wikipedia, "Diocletian" (CC BY-SA 4.0), which cites: Williams 1985, p. 26 (original not read by us) en.wikipedia.org
Wikipedia, "Diocletian" (CC BY-SA 4.0), which cites: Corcoran 2006, p. 39; Cambi, "Diokletian und die Tetrarchie", De Gruyter, 2012, p. 38–45 (we also read that source) en.wikipedia.org

Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Diocletian (contributors), used under CC BY-SA 4.0; this entry is available under the same licence. Other sources were used for facts only; no text or images are copied from them.