Year284 (CCLXXXIV) was aleap year starting on Tuesday of theJulian calendar. At the time, it was known as theYear of the Consulship of Carinus and Numerianus (or, less frequently,year 1037Ab urbe condita). The denomination 284 for this year has been used since the early medieval period, when theAnno Dominicalendar era became the prevalent method in Europe for naming years.
EmperorNumerian travels throughBithynia (Asia Minor) on his way home toRome. Suffering from aninflammation of the eyes, he travels in a closedlitter in which soldiers find his decaying corpse.
November 20 – The commander of Numerian'sdomestici (household troops),Diocles, is chosen to be the new emperor. In a military assembly outsideNicomedia (modernİzmit, Turkey), Diocles claims that the praetorian prefect (and rival for the throne) Arrius Aper murdered Numerian, and he personally stabs and kills the prefect on the spot. The new emperor changes his name to the Latinised 'Diocletian'. Building on existing trends, Diocletian presents his rule as that of a god-likedominus or autocrat.
Sabinus Julianus, the praetorian prefect of EmperorCarinus, exploits the instability and usurps the throne in northern Italy.
King of KingsBahram II installsMirian III, of the House of Mihran, on the throne of theKingdom of Iberia. Mirian would rule the kingdom until his death in c. 361.
