Editing 305 (section)

==== Roman Empire ====
* [[May 1]] &ndash; Emperor [[Diocletian]] abdicates and retires to his [[Diocletian's Palace|palace]] at [[Salona]] (modern [[Split, Croatia|Split]]) on the [[Adriatic Sea|Adriatic coast]], after a reign of nearly 21 years, in which the last vestiges of [[Roman Republic|republican]] government have disappeared.<ref>{{cite web |last=Cousin |first=Jean |title=Diocletian |url=https://www.britannica.com/biography/Diocletian |access-date=February 23, 2024 |series=Encyclopædia Britannica}}</ref>
* [[Maximian]] retires from office, and leaves for [[Campania]] or [[Lucania]] ([[southern Italy]]), to live a life of ease in his luxury [[Roman villa|villas]].
* [[Constantius I]] and [[Galerius]] are declared [[Augustus (title)|Augusti]]; [[Flavius Valerius Severus]] and [[Maximinus Daza]] are appointed [[Caesar (title)|Caesars]].
* Constantius requests leave for his son [[Constantine the Great|Constantine I]] to join him in the west, who has been living at the courts of Diocletian and Galerius as a hostage. Galerius allows Constantine to return.
* Summer &ndash; Constantine joins his father at Bononia ([[Boulogne-sur-Mer|Boulogne]]) in [[Gaul]]; they cross the [[English Channel|Channel]] to [[Roman Britain|Britain]] and make their way to [[Eboracum]] ([[York]]), capital of [[Britannia Secunda]] and home to a large [[military base]]. They campaign with success against the [[Picts]].
* Galerius begins a series of campaigns against the [[Sarmatians]], winning his first victory before the end of the year.
* Maximinus Daza persecutes the Christians of [[Roman Egypt|Egypt]], many of whom take refuge in the [[desert]]. In time, this refuge leads to the [[monastic]] life. In these monasteries, [[Coptic language|Coptic]] writing develops, supporting the propagation of Christian texts.
* [[Patron saint|Patron]] of [[Pozzuoli]], [[Proculus of Pozzuoli|Saint Proculus]], and patron of [[Naples]], [[Januarius|Saint Januarius]] are thrown to wild beasts in Pozzuoli's [[Flavian Amphitheater (Pozzuoli)|Flavian Amphitheater]], then beheaded at [[Solfatara (volcano)|Solfatara]].
* In this or the following year, the [[Baths of Diocletian]] are dedicated; the ''[[thermae]]'' become the largest imperial baths in Rome.