Editing Diocletian (section)

===Conflict in the Balkans and Egypt===
[[File:Philae, Trajan's Kiosk, Aswan, Egypt, Oct 2004.jpg|thumb|A [[Trajan]]ic temple on the island of [[Philae]], the newly established border between the [[Nobatae]] and [[Blemmyes]] and [[Roman Egypt]]{{sfn|Barnes|1981|pp=17–18}}]]
Diocletian spent the spring of 293 travelling with Galerius from Sirmium ([[Sremska Mitrovica]], [[Serbia]]) to [[Byzantium]] ([[Istanbul]], [[Turkey]]). Diocletian then returned to Sirmium, where he remained for the following winter and spring. He campaigned successfully against the Sarmatians in 294, probably in the autumn.{{sfn|Odahl|2004|p=59}} The Sarmatians' defeat kept them from the Danube provinces for a long time. Meanwhile, Diocletian built forts north of the Danube,{{sfnm|1a1=Barnes|1y=1981|1p=17|2a1=Williams|2y=1985|1pp=76–77}} part of a new defensive line called the ''Ripa Sarmatica'', at [[Aquincum]] ([[Budapest]], [[Hungary]]), Bononia ([[Vidin]], Bulgaria), Ulcisia Vetera, Castra Florentium, Intercisa ([[Dunaújváros]], Hungary), and Onagrinum ([[Begeč]], Serbia).{{sfn|Williams|1985|p=76}} In 295 and 296 Diocletian campaigned in the region again, and won a victory over the Carpi in the summer of 296.{{sfnm|1a1=Barnes|1y=1981|1p=17|2a1=Odahl|2y=2004|2p=59|3a1=Southern|3y=2001|3pp=149–150}} Later during both 299 and 302, as Diocletian was residing in the East, it was Galerius's turn to campaign victoriously on the Danube. By the end of his reign, Diocletian had secured the entire length of the Danube, provided it with forts, bridgeheads, highways, and walled towns, and sent fifteen or more legions to patrol the region; an inscription at [[Sexaginta Prista]] on the Lower Danube extolled restored tranquility to the region.{{sfn|Carrié|Rousselle|1999|pp=163–164}} The defense came at a heavy cost but was a significant achievement in an area difficult to defend.{{sfn|Williams|1985|p=77}}
[[File:Roman fresco on the southern wall of the cult chamber in Luxor temple depicting dignitaries revering the emperor, 4th century AD, Egypt.jpg|thumb|Roman fresco on the southern wall of [[Luxor Temple|Luxor Temple's]] imperial cult chamber. It depicts senior military officers gathered around Diocletian's throne, circa 280.<ref>{{Cite web |title=Chapel of Imperial Cult |url=https://madainproject.com/chapel_of_imperial_cult |access-date=24 December 2023 |website=Madain Project |language=en}}</ref><ref>{{Cite book |last1=Davenport |first1=Caillan |url=https://books.google.com/books?id=ycbYEAAAQBAJ |title=The Roman Imperial Court in the Principate and Late Antiquity |last2=McEvoy |first2=Meaghan |date=23 January 2024 |publisher=Oxford University Press |isbn=978-0-19-286523-6 |pages=86–87 |language=en}}</ref>]]
Galerius, meanwhile, was engaged during 291–293 in disputes in [[Upper Egypt]], where he suppressed a regional uprising.{{sfn|Carrié|Rousselle|1999|pp=163–164}} He returned to Syria in 295 to fight the revanchist Persian empire.{{sfn|Barnes|1981|p=17}} Diocletian's attempts to bring the Egyptian tax system in line with Imperial standards stirred discontent, and a revolt swept the region after Galerius's departure.{{sfnm|1a1=Barnes|1y=1981|1p=17|2a1=Southern|2y=2001|2pp=160, 338}} The usurper [[Domitius Domitianus]] declared himself ''Augustus'' in July or August 297. Much of Egypt, including [[Alexandria]], recognized his rule.{{sfn|Barnes|1981|p=17}} Diocletian moved into Egypt to suppress him, first putting down rebels in the [[Thebaid]] in the autumn of 297,{{sfn|Odahl|2004|p=59}} then moving on to besiege Alexandria. Domitianus died in December 297,{{sfn|DiMaio|1997}} by which time Diocletian had secured control of the Egyptian countryside. Alexandria, whose defense was organized under Domitianus's former ''[[Corrector#Roman Antiquity|corrector]]'' [[Aurelius Achilleus]], held out probably until March 298.{{sfn|Barnes|1981|p=17}}{{sfn|DiMaio|1997}} Later in 298, the [[triumphal column]] now known as [[Pompey's Pillar (column)|Pompey's Pillar]] was erected in Alexandria to honor Diocletian.{{sfn|Delbrück|2007|pp=100–101}}

Bureaucratic affairs were completed during Diocletian's stay:{{sfnm|1a1=Barnes|1y=1981|1pp=17–18|2a1=Southern|2y=2001|2p=150}} a census took place, and Alexandria, in punishment for its rebellion, lost the ability to mint independently.{{sfn|Southern|2001|p=150}} Diocletian's reforms in the region, combined with those of [[Septimius Severus]], brought Egyptian administrative practices much closer to Roman standards.{{sfn|Harries|1999|p=173}} Diocletian travelled south along the Nile the following summer, where he visited [[Oxyrhynchus]] and [[Elephantine]].{{sfn|Southern|2001|p=150}} In Nubia, he made peace with the [[Nobatae]] and [[Blemmyes]] tribes. Under the terms of the peace treaty Rome's borders moved north to [[Philae]] and the two tribes received an annual gold stipend. Diocletian left Africa quickly after the treaty, moving from Upper Egypt in September 298 to Syria in February 299. He met with Galerius in Mesopotamia.{{sfn|Barnes|1981|pp=17–18}}