Editing Maximian (section)

==Appointment as Caesar<!--'First division of the Roman Empire' and 'First partition of the Roman Empire' redirect here-->==
At [[Mediolanum]] ([[Milan]], [[Italy]]) probably in July 285, Diocletian appointed Maximian as his heir-apparent and subordinate, with the title ''Caesar''.<ref>The event has been dated to both 21 July ({{harvnb|Barnes|1981|p=6}}; {{harvnb|Barnes|1982|p=4}}; {{harvnb|Bowman|2005|p=69}}) and 25 July ({{harvnb|Potter|2004|pp=280–81}}). On the whole debate, see {{harvnb|Kuhoff|2001|pp=31–34}}. Another likely date is 13 December 285, following {{harvnb|Nixon|Rodgers|2023|pp=46–50}}.</ref> The reasons for this decision are complex. With conflict in every province of the Empire, from Gaul to Syria, from Egypt to the lower Danube, Diocletian needed a lieutenant to manage his heavy workload.{{sfnm|1a1=Barnes|1y=1981|1p=6|2a1=Rees|2y=2002|2p=30|3a1=Southern|3y=2001|3p=136}} Historian Stephen Williams suggests that Diocletian considered himself a mediocre general and needed a man like Maximian to do most of his fighting.{{sfn|Williams|1997|p=45}}

The general consensus is that Maximian was appointed ''Caesar'' before being proclaimed ''Augustus'' (the official term for "emperor"), as stated by the contemporary writer [[Eusebius]]. However, some modern scholars have doubted this, as there is virtually no evidence for this.{{sfn|Southern|2001|p=142, "It has also been suggested that Maximian became Augustus at the very beginning of Diocletian’s reign. The chronology is not established  beyond doubt"}} Even brief ''Caesars'' like [[Volusianus]] and [[Numerian]], who only held the title for a few months, had coins minted in their names. Historian Richard Burgess argues that Maximian was never ''Caesar'', and that his appointment as ''Augustus'' actually took place on 13 December 285, as opposed to the traditional date of 1 April 286, which has already been put into question by other authors.{{sfn|Burgess|2023}}

[[File:Istanbul - Museo archeol. - Diocleziano (284-305 d.C.) - Foto G. Dall'Orto 28-5-2006.jpg|thumb|right|[[Diocletian]], Maximian's senior colleague and Augustus in the east.]]
Diocletian was vulnerable in that he had no sons, just a daughter, Valeria, who could never succeed him. He was forced therefore to seek a co-ruler from outside his family and that co-ruler had to be someone he trusted.{{sfnm|1a1=Potter|1y=2004|1p=280|2a1=Southern|2y=2001|2p=136|3a1=Williams|3y=1997|3p=43}} The historian [[William Seston]] has argued that Diocletian, like heirless emperors before him, adopted Maximian as his ''filius Augusti'' ("Augustan son") upon his appointment to the office. Some agree, but the historian [[Frank Kolb]] has stated that arguments for the adoption are based on misreadings of the papyrological evidence.{{sfnm|1a1=Bowman|1y=2005|1p=69|2a1=Odahl|2y=2004|2pp=42–43|3a1=Southern|3y=2001|3pp=136, 331|4a1=Williams|4y=1997|4p=45}} Maximian did take Diocletian's ''[[Roman naming conventions#Nomen|nomen]]'' ([[family name]]) Valerius, however.{{sfn|Bowman|2005|p=69}}

Finally, Diocletian knew that single rule was dangerous and that precedent existed for dual rulership. Despite their military prowess, both sole-emperors Aurelian and Probus had been easily removed from power.{{sfn|Potter|2004|p=280}} In contrast, just a few years earlier, the emperor [[Carus]] and his sons had ruled jointly, albeit not for long. Even the first emperor, [[Augustus]], (r. 27 BC–AD 14), had shared power with his colleagues and more formal offices of co-emperor had existed from [[Marcus Aurelius]] (r. 161–180) on.{{sfn|Corcoran|2006|p=40}}

The dual system evidently worked well. Around 287, after Maximian's appointment as ''[[Augustus (title)|Augustus]]'', the two rulers' relationship was re-defined in religious terms, with Diocletian assuming the title ''Iovius'' and Maximian ''Herculius''.{{sfnm|1a1=Corcoran|1y=2006|1p=40|2a1=Liebeschuetz|2y=1979|2pp=235–52, 240–43|3a1=Odahl|3y=2004|3pp=43–44|4a1=Rees|4y=2002|4pp=32–33}} The titles were pregnant with symbolism: Diocletian-[[Jupiter (mythology)|Jove]] had the dominant role of planning and commanding; Maximian-[[Hercules]] the [[hero]]ic role of completing assigned tasks.{{sfnm|1a1=Barnes|1y=1981|1pp=11–12|2a1=Corcoran|2y=2006|2p=40|3a1=Odahl|3y=2004|3p=43|4a1=Rees|4y=2002|4pp=32–33, 39, 42–52|5a1=Southern|5y=2001|5pp=136–37|6a1=Williams|6y=1997|6pp=58–59}} Yet despite the symbolism, the emperors were not "gods" in the [[Imperial cult (ancient Rome)|Imperial cult]] (although they may have been hailed as such in Imperial panegyrics). Instead, they were the gods' instruments, imposing the gods' will on earth.{{sfn|Barnes|1981|p=11}} Once the rituals were over, Maximian assumed control of the government of the West and was dispatched to Gaul to fight the rebels known as Bagaudae while Diocletian returned to the East.{{sfnm|1a1=Barnes|1y=1981|1p=6|2a1=Southern|2y=2001|2p=137|3a1=Williams|3y=1997|3pp=45–46}}