Key to Umbria

Maximian’s Early Career


Maximianus Herculius (ca. 300 AD) from the Roman villa of Chiragan

Musée Saint-Raymond, Toulouse, France

According to the ‘Epitome de Caesaribus’ :

  1. “Aurelius Maximian, with the cognomen Herculius, was fierce by nature, burning with lust, stolid in his counsels, of rustic and Pannonian stock.  For even now, not far from Sirmium [now Sremska Mitrovica in Serbia, some 55 km west of Belgrade], there is a spot prominent because of a palace constructed there, where his parents once worked as wage-earners (exercebant opera mercenaria).  He died at the age of 60, imperator for 20 years.  From Eutropia, a Syrian woman, he sired Maxentius and Fausta, the wife of [the future Emperor] Constantine, to whose father, Constantius, he had given his stepdaughter, Theodora” (40: 10-2).

If Maximian really was aged 60 when died in 310 AD, he was born in 250 AD.

Although many early sources (including the ‘Epitome de Caesaribus’  above) identify Theodora as Maximian’s stepdaughter, some scholars reject this, arguing (with Timothy Barnes, referenced below, 1982, at p 33) that these all rely on a single and mistaken source.  Instead, these scholars accept the relationship as described in the ‘Origo Constantini Imperatoris’, which related to Theodora’s marriage

  1. “[Constantius] put away his former wife Helena and married Theodora, daughter of Maximianus ...” (1:2).

Maximian’s children seem to have been born over a relatively long period: Barnes (at p 33-4) estimated that Theodora was born in ca. 275 AD while Maxentius and Fausta were born in the period ca. 283-90 AD.  This suggests that Maximian was probably married twice. 

  1. If we assume that Theodora was about 18 years old when she married Constantius (an event that took place in ca. 288 AD - see below), we can reasonably date Maximian’s putative first marriage to ca. 270 AD.  Timothy Barnes (as above, at p 34) suggested that this unknown first wife of Maximian might have been a daughter of Afranius Hannibalianus (see below).

  2. Based on the probable ages of Maximian’s younger children, we can reasonably date his marriage to Eutropia to ca. 283 AD.

Thus, it seems likely that both marriages took place before his elevation to the imperial college.

What is known of Maximian’s early career is largely derived from a panegyric (Panegyric X, translated into English in Nixon and Rodgers, referenced below) that was delivered at his court, probably at Trier and probably in 289 AD.  This confirmed that he had been born in Pannonia (2:2) and recorded that he had risen through the ranks of the imperial army: on the Danube (2:4); and then on the Euphrates (2:6).   Maximian’s service on the Euphrates had presumably taken place during the campaign of the Emperor Aurelian against Queen Zenobia of Palmyra in 272 AD.  He presumably continued to serve under the Emperor Carus, and might well have demonstrated his loyalty to Diocletian during the events that followed Carus’ death and led to Diocletian’s acclamation.

Maximian’s Elevation

As noted on the previous page, Aurelius Victor recorded that:

  1. “... when Diocletian had learned [of the revolt of the Bagaudae in Gaul] ... he immediately appointed as Emperor (imperatorem iubet) Maximian, a loyal friend who, although he was rather uncivilised, was nevertheless a good soldier of sound character” (‘De Caesaribus’, 39:17).

C. E. V. Nixon (in Nixon and Rodgers, referenced below, at page 46) observed that:

  1. “the appointment of Maximian to command an expeditionary force with some kind of imperial powers in order to suppress the Bagaudae in Gaul .... [constituted Diocletian’s first step towards collegiate rule]”.

This was an unprecedented response, since the two men were unrelated, and we might reasonably conclude (as noted on the previous page) that Diocletian perceived the Gallic revolt as a precursor to secession and a serious threat to his continued hold on power.

Maximian’s Imperial Appointment(s)

On the previous page, attention was drawn to a coin (RIC V:II 203) that was minted for Diocletian at Ticinum (Pavia) soon after the death of Carinus, which had the reverse legend ‘ADVENTUS AUG’.  Thus the newly victorious Diocletian certainly made a ceremonial entry into Milan, probably in the summer of 285 AD.  Timothy Barnes (referenced below, 1982, at p 57) suggested that this was the most likely occasion on which he appointed Maximian as his imperial colleague: thereafter, he moved to the Danube frontier while Maximian moved to Gaul, and their next face-to-face meeting did not apparently take place until 288 AD (see below).

The early sources differ as to the nature of Maximian’s initial imperial appointment.  Aurelius Victor (above) had him appointed as Emperor.  However, Eutropius whose account of these events was otherwise essentially the same as that of Aurelius Victor, differed on this important detail:

  1. “... when the peasants in Gaul made an insurrection, giving their faction the name of Bagaudae and having for leaders Amandus and Aelianus, [Diocletian] despatched Maximian Herculius, with the authority of Caesar, to suppress them” (‘Breviarium historiae Romanae’ 9:20). 

C. E.. V. Nixon (in Nixon and Rodgers, referenced below, at page 47) pointed out that there is no unambiguous evidence, from coins, papyri or inscriptions, for Maximian as Caesar.  Thus one is left to decide between conflicting literary sources.  Fortunately, there is corroborative evidence in favour of Eutropius in the official imperial titles.  For example, in the Price Edict of 301 AD (reproduced by Timothy Barnes, 1982, at p 19):

  1. Diocletian had the victory titles Germanicus Maximus VI and Sarmaticus Maximus VI; while

  2. Maximian had the victory titles Germanicus Maximus V and Sarmaticus Maximus V.

Diocletian and Maximian certainly shared their victory titles once Maximian held the rank of Augustus, so Diocletian’s first victory against the Germans and his first victory against Sarmatians must have pre-dated this.  The most obvious inference is that these belonged to Maximian’s period as Caesar (with Diocletian taking credit for his own victory against the Sarmatians on the Danube and that of his Caesar against the Germanic tribes on the Rhine).  This indeed is the conclusion reached by Timothy Barnes, summarised in Table 5, p 255.

An epigraphic analysis of Maximian’s tribunician power throws further light on his precise status during his (probable) period as Caesar: R. E. Smith (referenced below, at p 1060) demonstrated that he could not have had tribunician power before 10th December 285 AD because it was renewed for the first time on this date in the following year.  The most obvious sequence of events is that he became Caesar without tribunician power during a meeting with Diocletian at Milan in the summer of 285 AD and was elevated to the rank of Augustus with tribunician power at some time before 10th December 286 AD.  In the months between these two appointments (when Diocletian alone claimed victory titles) the title of Caesar simply (but importantly) designated him as Diocletian’s chosen successor.

The date of Maximian’s putative promotion to the rank of Augustus is unknown, although (as noted above) it had certainly occurred by 10th December 286 AD:

  1. The (sometimes unreliable) ‘Consularia Constantinopolitana’ dates it on 1st April 286 AD, and many scholars accept this.

  2. Timothy Barnes (referenced below, 1982, at p 4, note 6) tentatively accepted it, although he noted that:

  3. “The earliest indubitable attestations of Maximian as Augustus appear to be on 24th May ... and 12th June 286 AD ...”

  4. According to C. E. V. Nixon (in Nixon and Rodgers, referenced below, at page 48):

  5. “Alexandrian coins confirm that [Maximian] was Augustus before 28th August 286 AD”.

  6. According to David Potter (referenced below, 2013, at p 33):

  7. “....Maximian defeated [the Bagaudae] and then moved on to the Rhine, where he had to deal with a wide variety of raiders, and it was at the end of 286 AD that Diocletian recognised his achievements by raising him to the rank of co-Emperor or Augustus”.

The main difficulty with the hypothesis that Maximian was originally designated Caesar is that there is no obvious occasion during 286 AD on which the two men might have been in the same place at the same time in order to celebrate his putative promotion: one would reasonably assume that such a promotion would have been the subject of a great deal of ceremonial and that this great event would have been referred to (for example) in later panegyrics.  Some earlier scholars suggested that Maximian had unilaterally arranged to be acclaimed as Augustus, and that Diocletian had had no option but to accept the situation.  However, nothing in Maximian’s future relationship with Diocletian suggests that he would have behaved in this way.  My own view (for what it is worth) is that, whether or not there was a public ceremony, Diocletian elevated Maximian as a matter of conscious policy, probably because: (a) he needed Maximian and wanted to secure his loyalty; and (b) he had come  to appreciate that the continued loyalty of the people of Gaul demanded a constant imperial presence in its traditional capital at Trier.


Timothy Barnes (referenced below, 1982, at p 4) established the official names of the Augusti as:

  1. Gaius Aurelius Valerius Diocletianus (Diocletian); and

  2. Marcus Aurelius Valerius Maximianus (Maximian).

In a later work (referenced below, 2011, at p 29), Timothy Barnes suggested that, Maximian’s name had been Marcus Aurelius Maximianus before he joined the imperial college.  This is perfectly possible: these names were common, particularly among families that had been given Roman citizenship under the the Emperor Marcus Aurelius Severus Antoninus (Caracalla) in 212 AD.  Barnes further suggested that:

  1. “When [Diocletian] co-opted Marcus Aurelius Maximianus as his imperial colleague, he added Aurelius to his own nomenclature, while Maximian added Valerius to his, so that they both now had the double family name of Aurelius Valerius”.

Pierfrancesco Porena (referenced below, 1982, at p 112-3, my translation) was more specific:

  1. “The evidence of inscriptions and papyri seems to indicate that ‘Aurelius’ was placed before ‘Valerius’ in Diocletian’s official name at the time of the nomination of Maximian as Augustus.  This was a natural consequence of the relationship that Diocletian had instituted with Maximian by this promotion: the Augusti considered themselves to be brothers, and they wanted to make this explicit in their official names.  Thus, each absorbed the name of his colleague, becoming C.  Aurelius Valerius Diocletianus and M. Aurelius Valerius Maximianus”.

There is indeed no evidence that Diocletian formally adopted Maximian, and it is clear that the two men routinely referred to themselves as brothers.  Nevertheless, there was no doubt that Diocletian was the senior partner, and (as we shall see) Maximian’s behaviour suggested that he was entirely comfortable with this arrangement.

Jovius and Herculius

According to Aurelius Victor, soon after Diocletian had appointed him as Augustus (in 285 AD):

  1. “[Maximian] received the [signum] Herculius from his worship of that deity, just as [Diocletian] received that of Jovius.  This was the also the origin of the names given to those auxiliary units which were particularly outstanding in the army” (De Caesaribus’, 39:14).

These additions to the imperial names indicate that Diocletian and Maximian were (respectively) ‘of Jove’ and ‘of Hercules, implying that each enjoyed the patronage of his associated deity. 

Joshua Petitt (referenced below), who made a detailed study of the way in which these signa were actually used, concluded from the epigraphic record that:

  1. “the [signa] were not necessarily an official part of the imperial title, but they were recognised as acceptable references to the [corresponding] emperor”

Thus, the following inscription CIL III 3231 from Sirmium:

I(ovi) O(ptimo) M(aximo) et / G(enio) h(uius) l(oci)

pro / salute dd(ominorum) / nn(ostrorum) Iovio(rum) / et Herculio(rum)

Augg(ustorum) nn(ostrorum)

would have been easily understood as a dedication made to Jupiter Optimus Maximus for the health of Diocletian and Maximian, identified here only as the Jovian and Herculian Augusti.

The significance of these signa is difficult to ascertain.  The most usual explanation is that articulated by C.E.V. Nixon( in Nixon and Rodgers, referenced below, at p 44-5):

  1. “As well as constituting a claim to the powerful support of the Olympians, the names might be intended to symbolise the relationship between Diocletian and Maximian, [with] Diocletian acting as a father figure to his Herculian assistant”.

Joshua Petitt considered other factors that might have led Diocletian to introduce the signa:

  1. He  suggested (at p  48) that Diocletian’s association with Jove, taken together with his military reforms, would have bolstered his position with the legions. 

  2. He also suggested (at p 49) that the adoption of these signa would have made clear the fact that there was no room in the imperial college for the rebel Carausius (below), who had been acclaimed in Britain in 286 or 287 AD.

Stephen Williams (referenced below, at p 69) articulated what was perhaps the most compelling reason for the use of the signa, which was a generalisation of the point about Carausius made above:

  1. “[The most important reason for] this powerful new religious emphasis was the need ... to break with the dangerous tradition that the armies had the right to make Emperors.  If legitimacy ... did not derive from the armies, and not from the Senate, there was only one other source: the gods.”

Joshua Petitt made another interesting suggestion: perhaps Maximian’s association with Hercules had begun before Diocletian formalised the situation by means of the quasi-official signa ??  While this is necessarily a matter of speculation, the related idea that Maximian’s association with Hercules was particularly strong is discussed further in my page on Maximian’s Herculian Dynasty.

Praetorian Prefects (286-93 AD)

An inscription (LSA 366, now in the Archaeological Museum, Sofia), which came from military camp of Oescus on the Danube (in modern Bulgaria), is fundamental for the understanding of Diocletian’s policy in appointing Praetorian Prefects.  This inscription is on a structure commissioned by a pair of Praetorian Prefects, which erved as either a base for a statue of Diocletian or as an altar dedicated to his divine spirit and majesty.  

Imp(eratori) Caes(ari) C(aio) Aurel(io) / Val(erio) Diocletiano

p(io), f(elici), invic(to) Aug(usto), pon[t(ifici)] / max(imo), Germanic[o]

max(imo) trib(uniciae) potes[t(atis)] / p(atri) p(atriae), proco(n)s(uli)

Afranius Hanni/balianus, Iul(ius) As[c?]/lepiodotus

v(iri) / emm(inentissimi), prae[f(ecti) pr(aetorio)]

d(evoti) n(umini) m(aiestati) [q(ue) e(ius)]

To the Emperor Caesar Caius Aurelius Valerius Diocletianus

pious, fortunate, unconquered Augustus, pontifex maximus, victorious over the Germans

holder of tribunician power, father of the fatherland, proconsul

Afranius Hannibalianus [and] Julius Asclepiodotus,

both of senior equestrian rank, Praetorian Prefects

devoted to [Diocletian’s] divine spirit and majesty, [set this up]

Afranius Hannibalianus and Julius Asclepiodotus were viri emminentissimi, the rank that was conventionally awarded to members of the equestrian order who had achieved this prestigious position.   The inscription must predate 292 AD, when they became viri clarissimi on their designation as Consuls for that year.

More precise dating can be deduced from the names and tiles applied to Diocletian.  Unfortunately, the inscription does not specify how many times his tribunician power had been renewed: this could mean that the inscription pre-dated its first renewal, but that is unlikely since, as Timothy Barnes (referenced below, 1982, at p25) explained, the first renewal took place only 19 days after his acclamation (with annual renewals thereafter).  Thus, it seems more likely that the number of renewals by the time of the inscription had simply been omitted.  However, the official name Caius Aurelius Valerius Diocletianus is more useful: as noted above, it probably implies a date after Maximian’s elevation to the rank of Augustus in 286 AD.  Diocletian’s single victory title of Germanicus Maximus implies a date early in his reign: more specifically, as noted above, it probably relates to a victory that Maximian had secured as Caesar.  It is therefore  entirely possible that this and a twin inscription dedicated to Maximian commemorated his subsequent elevation in 286 AD.

It is interesting to speculate about the possible dates upon which the respective Praetorian Prefects had been appointed:

  1. Since Afranius Hannibalianus is named before Julius Asclepiodotus, it is reasonable to assume that he had been appointed first.  The most natural hypothesis is that this had occurred soon after the acclamation of Diocletian in November 284 AD (the occasion on which he had apparently executed Numerian’s Praetorian Prefect, Aper). 

  2. We know from Aurelius Victor that Aurelius Aristobulus, the Praetorian Prefect of Carinus at the time of his murder in the summer of 285 AD, remained in this position under Diocletian.  Thus, we can reasonably assume (with Pierfrancesco Porena) that Julius Asclepiodotus replaced him at the time of Maximian’s elevation. 

Thereafter, Afranius Hannibalianus was presumably assigned to Diocletian and Julius Asclepiodotus to Maximian (just as Aper and Aurelius Aristobulus had been assigned (respectively) to Carus/Numerian and Carinus in the previous reign).

As noted above, both men were honoured by designation as the Consuls of 292 AD.  As set out on the following page, they remained in place as the only two Praetorian Prefects when two Caesars were added to the imperial college in the following year.

Diocletian’s Campaigns (285-8 AD)

Danube Frontier

It seems likely that the security of the frontier on the Danube had been compromised in the period immediately after the death of the Emperor Probus in 282 AD, which had allowed an Indo-European people known as the Sarmatians to cross the Danube.  Thus, according to Eutropius:

  1. “After the death of Probus, Carus was created emperor ... News being brought [to him], while he was engaged in a war with the Sarmatians, of an insurrection among the Persians, he set out for the east ... (‘Breviarium historiae Romanae’, 9:18).

The Sarmatian problem was thus left unresolved and, as Hrvoje Gračanin (referenced below) pointed out:

  1. “Often, breaches of the frontier defences as a result of barbarian incursions could provide local commanders ... with an opportunity to fish in troubled waters.”

In fact, the ‘fisherman’ on this occasion had been a local official, Julianus, who took control of Pannonia (as the Augustus Marcus Aurelius Julianus) until he was defeated by the Emperor Carinus in 284-5 AD.  Hrvoje Gračanin (referenced below) observed:

  1. “... was a clear sign for Diocletian [after his defeat of Carinus] that something had to be done about Illyricum so as to prevent further political turmoil in the area that could undermine his own position in the future.”

The task here was almost exactly paralleled by that in Gaul, which Diocletian had recently delegated to Maximian (above): the main difference was that, while the Danube frontier had witnessed countless usurpations during the previous decades, it had not experienced a prolonged period of independence.

Diocletian seems to have accomplished his immediate objectives with a successful campaign against the Sarmatians soon after his accession.  Unfortunately, the only surviving evidence for this comes from the first of Diocletian’s four victory titles as ‘Sarmaticus Maximus’.  Maximian did not share this title, which indicates that it predated his elevation as Augustus, and  Timothy Barnes (referenced below, 1982, in Table 5, p 255) therefore dated the victory to 285 AD.   Timothy Barnes (referenced below, 1982, p 50) and, more recently, Péter Kovács (referenced below), associated this campaign with two imperial edicts (CJ 4.48.5 and Frag. Vat. 297) issued on 2nd November 285 at (respectively) at ‘Atubino’ and ‘Suneata’, probably Civitas Iovia (Botivo) and Sonista in Pannonia superior.  However, as observed;

  1. “Because of lack of time (Diocletian ... spent the winter in Nicomedia), [this expedition] had to be rather short and demonstrative”.


Persia was the only neighbouring state whose power approached (and had sometimes surpassed) that of Rome.  However, King Vahran II of Persia (whose name is also spelt Vahram or Bahram) had recently been undermined by the revolt of his brother Hormizd, which explains the success of the Emperor Carus in Persia in 284 AD.  Diocletian, who had taken part in this campaign, was well aware of the continuing opportunities presented by Vahran’s difficulties. 

Timothy Barnes (referenced below, 1982, at p 50-1) presented the evidence for his presence in the east (in Palestine and Syria) in 286-7 AD (when the Danube frontier was at least temporarily secure).  This seems to have been associated with a show of strength that intimidated Vahran into making concessions: thus, in Panegyric X (above), the panegyrist could exult that:

  1. “the Persian realm voluntarily submitted itself to Diocletian.  ... he accomplished this in the manner of his Jupiter, at whose paternal nod all things tremble ... (7:5). 

  2. “[At their conference of 288 AD (below), Diocletian and Maximian had] magnified each other in turn, ...

  3. -[Diocletian] by displaying to [Maximian] gifts from the Persians; and

  4. -[Maximian] by by displaying to [Diocletian] spoils won from the Germans” (9:1).

  5. “... the Great King of Persia [Vahran II], who has never before deigned to confess that he is but a man, makes supplication to [Diocletian] and throws open the whole of his Kingdom to him, if he should consider it worthy to enter. ... Content to request the name of friend, he earns it by his submission” (10: 6-7).

The precise nature of Vahran’s concessions is unclear:

  1. He might have  conceded territory in Mesopotamia that had been previously but temporarily regained by Carus, although this is a matter of dispute among scholars.  (See notes 30 and 36 to the translation of Panegyric X).

  2. He more certainly restored part of Armenia to King Tiridates III, was able to return to power there in has traditional rôle as a Roman client.  (Dodgeon and Lieu, referenced below, list the Armenian sources at 5.2.4, p122, with translations in their Appendix II).

Maximian in Gaul (285-8 AD)

Revolt of the Bagaudae

As set out above, Maximian’s first task was to deal with the revolt of the Bagaudae.  Timothy Barnes (referenced below, 1982, at p 57) dated Maximian’s suppression of this revolt to late 285 AD, although Percy Webb (referenced below, at p 579 ) suggested that it continued into the following year.  In Panegyric X (above), the panegyrist made only passing reference to this success, explaining:

  1. “This I pass over in haste, for I see ... that you [Maximian] prefer that victory to be cast into oblivion rather than glorified” (4:4).

This is possibly because it had been secured against fellow-Romans and/or possibly because Maximian would not have wanted to draw attention to a recent example of ‘Gallic nationalism’. 

Barbarian Incursions

The panegyrist then described a series of significant incursions immediately after the above revolt, which:

  1. “threatened the destruction of the whole of Gaul: not only the Burgundians and Alamanni, but also the Chaibones and Eruli .... burst into these provinces in headlong assault” (5:1).

Maximian led a small army against the Chaibones and Eruli, who were:

  1. “.... cut to pieces and slaughtered in ...a massacre” (5:3).

Stephen Williams (referenced below, at p 50) suggested that this engagement took place in Germania Inferior (the Low Countries).  According to the panegyrist, Maximian allowed the rest of the enemy (presumably the Burgundians and Alamanni) to:

  1. “...[fall] prey to the extremes of famine, ... intending then to employ bands of troops to capture them to adorn [his] triumph” (5:2).

As noted above, this victory secured by Diocletian’s Caesar was probably the source of the first of his four titles as ‘Germanicus Maximus’ (summarised by Timothy Barnes, 1982, in Table 5, p 255).  It seems to have been shortly thereafter that Maximian was elevated to the rank of Augustus.

Revolt of Carausius

After listing Maximian’s past successes, the panegyrist (at 12:1) went on to discuss “that pirate”, a reference to Maus(aeus) Carausius, who had been one of Maximian’s generals duringf the revolt of the Bagaudae.  He seems to have had a particular aptitude for seamanship, and was therefore subsequently sent to rid the Channel of pirates, a task that he undertook successfully from his base at Bononia (modern Boulogne). However, according to Eutropius:

  1. “[H]aving captured numbers of the barbarians on several occasions, [Carausius had] never given back the entire booty to the people of the province nor sent it to the Emperors.  [This created the suspicion that] he had intentionally allowed the barbarians to congregate there, so that he might seize them and their booty as they passed and, by that means, enrich himself.  On being sentenced by Maximian to be put to death, [Carausius] assumed the imperial purple and the government of Britain” (‘Breviarium historiae Romanae, 9:21).

The list of Maximian’s successes in Panegyric X (above) ended with one that was obviously associated with these events:

  1. “It is thorough your good fortune ... [Maximian] that your soldiers have already reached the Ocean in victory, and that already the receding waves have swallowed up the blood of enemies slain on that shore” (11:7).

The translator (at note 41) noted that Maximian had clearly driven Carausius from Gaul, but he had been unable to pursue him across the Channel.  The reason for this incapacity emerged in a later panegyric (Panegyric VIII, translated into English in Nixon and Rodgers, referenced below, which was delivered at Constantius’ court, probably at Trier, in ca. 297 AD), in which the panegyrist explained that:

  1. “... the fleet that once guarded the Gauls was abducted by the pirate as he fled ...” (12:1).

The panegyrist conspicuously omitted to mention that “the pirate” Carausius had been commanding this fleet in the service of Maximian before his flight.  He did however record that Carausius had also seized a Roman legion (presumably that stationed at Bononia) and several auxiliary units, that he enjoyed the support of some Gallic merchants, and that, once established in Britain, he had been able to recruit barbarian mercenaries and expand his navy.

C. E. V. Nixon (in Nixon and Rodgers, referenced below, at page 50) pointed out that it is difficult to establish from the surviving sources whether Carausius’ revolt took place in 286 or in 287 AD.  However, after a thorough evaluation of the numismatic and literary evidence, John Casey (referenced below) proposed a scenario that reconciled some apparent conflicts between the various sources.  He suggested (at p 42-3) that the engagement in which Maximian drove Carausius from Gaul took place in the summer of 286 AD and that it represented an early phase of the revolt that was largely ignored in later accounts.  These accounts assigned the revolt proper to the following year, when Carausius had secured the support of the legions based in Britain and formally assumed the rank of Augustus there.  Thus, for example, it was in his entry in the “Chronicle” for the 4th year of Diocletian’s reign (i.e. 287 AD) that St Jerome recorded:

  1. “After assuming the purple, Carausius occupied Britain.”

As we shall see below, this usurpation of Britain continued for about a decade, and was one of the most serious challenges of Diocletian’s reign.

Alamanni Incursions

The year of 287 AD began dramatically: the inauguration of Maximian’s first consulship (as Diocletian’s colleague) at Trier was disrupted by news of further barbarian raids.  The panegyrist of 289 AD (above) remembered:

  1. “We saw you [Maximian] on the same day both in the most splendid garb of peace and in the magnificent accoutrements of war” (6:3).

This seems to have been a short engagement, but shortly afterwards, Maximian made:

  1. “.... that famous crossing .... [across the Rhine] into Germany” (7:1).

Stephen Williams (as above) described a major offensive against the Alamanni at this time, which involved a deep thrust into their territory, while Timothy Barnes (referenced below, 1981, at p 7) referred to a campaign across the Rhine that lasted for the whole campaigning season of that year.  As a result, the panegyrist of 289 AD could exclaim that:

  1. “... all I see beyond the Rhine is Roman” (7:7).

This was the source of Maximian’s first and Diocletian’s second title of ‘Germanicus Maximus’, which Timothy Barnes, (referenced below, 1982, in Table 5, p 255) dated to 287 AD. 

The panegyrist went on to record that Diocletian had:

  1. “... recently attacked that part of Germany that lies opposite Raetia [in the upper Danube] and by this victory extended the boundaries of Rome with a courage similar to yours [Maximian]” (9:1).

This suggests a pincer movement against the Alamanni, by Maximian from the north and by Diocletian from the south. 

It is possible that the future Caesar, Constantius, took part in this operation.  The fact that he enjoyed the patronage of Maximian in the years before his elevation is clear from a reference in Panegyric VIII (above), which was delivered at Constantius’ court, probably at Trier, in ca. 297 AD.  The panegyrist on this occasion recorded that:

  1. “... thanks to the favour of your divinity [Constantius], there occurred for me long ago that very access to the divine ears of your father [Maximian] that first brought me out into the public light” (1:5). 

Having received this favour, the panegyrist had then witnessed two successes of Constantius before his accession, while he was still serving in Gaul under Maximian.  These involved:

  1. “... the capture of a king of a most savage nation while he was in the act of preparing an ambush, and the complete burning and devastation of Alamannia from the Rhine bridge [probably at Mainz] right up to the crossing of the Danube at Giunta [probably modern Günzburg] ...” (2:1).

Timothy Barnes (referenced below, 2011, at p 39) suggested that this march by Constantius to the headwaters of the Danube might well have formed part of Diocletian’s part of the pincer movement.

Diocletian and Maximian (288 AD)

The panegyrist (above) described the subsequent meeting of the Augusti, who had:

  1. “... [come] together from opposite ends of the globe [and] clasped invincible hands.  How trusting and fraternal was that conference! “ (9:2).

This was probably their first meeting since Maximian’s elevation.  As the panegyrist reported:

  1. “At it ....

  2. -[Diocletian displayed] to you [Maximian] gifts that [he had received] from the Persians; and

  3. -you [displayed] to him spoils won from the Germans” (9:2).

Despite these formalities, this has the feel of a working meeting rather that a great set-piece occasion (unlike the meeting of 290 AD, described below).   Its main purpose must have been to plan a campaign for the destruction of Carausius (above).  Indeed, the pincer movement against the Alamanni (above) might well have been a precursor to such a campaign, designed to remove what might otherwise have been a significant distraction. 

The Augusti might also have discussed the fact that Maximian intended to link himself a senior member of his entourage through ties of marriage, an event that had taken place by the time that Panegyric X (above) was delivered:

  1. “You indeed, [Maximian], so earnestly hold that harmony is a virtue that you have bound to you by ties of friendship and marriage even those who perform the highest office of your entourage ... Under the leadership of such men, .... that pliant and treacherous race of barbarians was crushed as it deserved ..” (1:4).

Timothy Barnes (as above, at p 41) strongly supported the idea put forward by a number of other scholars that this was an allusion to the marriage of Constantius to Theodora, Maximian’s daughter, an event recorded in the ‘Origo Constantini Imperatoris

  1. “[Constantius] put away his former wife Helena and married Theodora, daughter of Maximianus ...” (1:2).

If this is correct, Constantius became Maximian’s son-in-law some five years before his promotion into the imperial college (which, as we shall see, occurred in 293 AD).

Although Panegyric X mentioned neither Constantius nor Theodora by name, it did mention Maximian’s young son Maxentius, who was probably in the audience:

  1. “But surely that day will soon dawn when Rome sees you victorious and, alert at your right hand, your son [Maxentius] ..., It will be no great labour for [his future tutor] to encourage in this divine and immortal scion a yearning for glory. ... [He will only need to] point out your deeds [Maximian] ... and  repeatedly ... display you as a living and best example  of the imperial system” (14: 1-2).

The expectation seems to have been that Maxentius, who was probably about six years old at this time, would be groomed to succeed Maximian in due course (as the translator pointed out at note 50). 

It is also impossible to determine whether Maximian’s new son-in-law, Constantius, was also considered as a potential successor at this point, and how his son, Constantine (who was perhaps 15 years old at this point) viewed his new stepmother (Theodora) and (more importantly, at least in political terms) his new relationship with her father (Maximian) and her young half-brother (Maxentius).  The way that these relationships played out was to come to the fore some two decades later.

Campaign against Carausius (288-9 AD)

Soon after Diocletian’s return to the east, Maximian undertook a campaign against the Franks, following which, according to Panegyric X (above):

  1. “Gennoboudes recovered his kingdom thanks to you [Maximian], indeed received it from you as a gift” (10:3).

The Frankish Gennoboudes was presumably reinstated as a client of Rome, in order to further ensure the security of the Rhine frontier ahead of the planned campaign against Carausius, and perhaps to reduce Carausius’ ability to recruit Frankish mercenaries.

By the time that Panegyric X was delivered (i.e. probably 289 AD), Carusius had escaped retribution and efficiently ruled an independent Imperium Britanniarum for some two years.  Carausius became the first Roman Emperor to mint in Britain, at London and another location that was probably Colchester.  He also established a mint in north west Gaul,probably at Rouen, but this seems to have been used only for a short period immediately after his revolt.  Carausius’ access to British silver allowed him to issue coins of higher quality than those of Diocletian’s pre-reform output, and this earned him the support of British and Gallic merchants.   He also seems to have added to his popularity by effectively policing the northern borders of Britain.  An inscription on a milestone from  Carlisle, which indicates the geographical extent of his control, reads: 

"IMP[eratori] C[aesari] M[arco]/ AVR[elio] MAVS[aeo ??]/ CARAVSIO

P[io] F[elici]/INVICTO AVG[usto]

For the Emperor Caesar Marcus Aurelius Maus(aeus) Carausius

Pius, Fortunate,  Invincible Augustus

(More than a decade after the death of Carausius (described on the following page) this end of the milestone was buried, after the other end had been inscribed:

Fl(avio) Val(erio) /Cons/tant[i-]/ no nob(ilissimo)/ Caes(ari)

Flavius Valerius Constantine, most noble Caesar [and future Emperor])

Despite Carausius’ success in the previous two years, the panegyrist claimed that Carausius was now terrified because: 

  1. “... he can see your armies on the point of penetrating [the Channel], which has been the only reason that his death has been delayed until now... The most beautiful fleets have been built, which are about to reach the ocean simultaneously from every river. ... Throughout almost the whole year, ... when you needed fine weather in order to construct the ships ... almost no day was marred by rain.  Winter itself [i.e. probably the winter of 288-9 AD] imitated the mildness of  Spring [the implication being that the gods looked down favourably on the enterprise]” (12:1-4). 

Later in the speech, the panegyrist made another reference to this expected engagement, in the context of a digression on the Temple of Hercules Victor in the Forum Boarium in Rome: 

  1. “This name [Hercules Victor] was once given to that god by the man who defeated pirates in a merchant vessel, and heard from Hercules himself, during his sleep, that he had won the victory with his help.  So it is [Maximian] that for many centuries it has been among the duties of your divinity to overcome pirates.  But surely the day will soon dawn when Rome sees you victorious ...” (13:5 - 14:1)”. 

This earlier scourge of pirates was Marcus Octavius Herrenus, who (according to Macrobius in his ‘Saturnalia’, 3: 6:10 and to Servius in his ‘ad Aeneid’, 8: 362-3  ) had dedicated a temple and statue of Hercules Victor in Rome after his victory. 

Maximian’s fleet must surely have set sail as advertised.  However, nothing more is heard of it: in particular, it is conspicuous by its absence in Panegyric XI (above), which was delivered at Maximian’s court, probably at Trier and probably in 291 AD.  It can only be assumed that this expedition ended in failure. 

Barbarian Settlement in Gaul

In Panegyric VIII (above), the panegyrist referred to Maximian’s measures to resettle barbarians in Gaul, where they cultivated land that would have otherwise been abandoned:

  1. “ your bidding, Maximian Augustus, [two groups of settled barbarians]:

  2. -the Laeti [who were] restored [to their land] by right of postliminium; and

  3. -the Franks [who were] admitted to our laws;

  4. have cultivated the empty fields of the Arvii [on the north west coast of Gaul] and the Treveri [around Trier]” (21:1).

These Laeti and the Frankish settlers seem to have had relatively favoured status:

  1. The translator (at note 76) pointed out that this mention of  the ‘Laeti’ is the earliest in our in surviving sources.  These settlers did not apparently belong to a particular tribe but were rather assigned to barbarian communities made up of of various ethnicities that owed military service to the Empire.  They continued as distinct communities at least into the following century.  Thus, according to Ammianus, the future Emperor Julian, who was then (in ca. 357 AD) the newly appointed Caesar and Governor of Gaul, offered to the Emperor Constantius II:

  2. “.... some young men of the Laeti, the progeny of barbarians spawned on [the Roman] side of the Rhine ...[for service in his (i.e. Constantius’) household guard]” (20:8:13, as translated in note 76, above).

  3. The date at which the first communities of Laeti had been established in Gaul is unknown. The fact that Maximian restored land to some of them by right of postliminium suggests that they enjoyed rights under Roman law.  It also implies that they had been expelled from their land by force, perhaps during the revolt of the Bagaudae in 285 AD.

  4. Maximian might have settled the Franks (who had also been “admitted to our laws”) in ca. 288 AD, when he had also restored the Frankish King Gennoboudes as a Roman client on the other side of the Rhine (above).

Diocletian’s Campaigns (288-90 AD)

Danube Frontier

As noted above, Diocletian fought a short and apparently successful campaign against the Sarmatians in Pannonia late 285 AD.  Unfortunately, as Stephen Williams (referenced below, at p 52) observed, although this campaign was recorded as a triumph:

  1. “... it gave a respite of only three years ... By 289 AD, the Sarmatians had to be fought again.”

Thus, in Panegyric XI (translated into English in Nixon and Rodgers, referenced below), which was delivered at Maximian’s court, probably at Trier and probably in 291 AD, the panegyrist spoke of:

  1. “... Sarmatia’s devastation ....” (5:4); and

  2. “Those laurels [won by Diocletian] from the conquered nations ....[including] Sarmatia” (7:1).

This later victory was the source of the second of Diocletian’s four titles as ‘Sarmaticus Maximus’, which Timothy Barnes (referenced below, 1982, in Table 5, p 255) dated to 289 AD.  

Nevertheless, the situation remained unstable, probably because of pressure on the Sarmatians and others who had settled on the frontier from other peoples intent on taking their land.  Thus, the panegyrist  lamented:

  1. “... our enemies’ insane mutual destruction throughout the world ... all peoples rush against their own kind, whose lot it never was to be Roman ...” (16: 3-5).

Among these conflicts:

  1. “the Tervingi too, another group of Goths, with the help of a band of Taifali, join battle with the Vandals and Gepids” (17:1).

This an extremely important (if obscure) passage, since it is the first known reference to the Gothic Tervingi and Taifali people and also to their enemy, the Gepids.  Péter Kovács (referenced below) suggested that the passage gave:

  1. “... the reason of the Sarmatian wars ... It was most probably the growing power of the Goths in the Carpathian basin [i.e. Pannonian Plain]”. 

Certainly, the context in which the conflict appears in the panegyric suggests that it was characteristic of the turmoil that was prompting the Sarmatians to try to take refuge on the Roman side of the Danube.  It was presumably in response to this pressure that Diocletian therefore established his main residence at Sirmium (now Sremska Mitrovica in Serbia, some 55 km west of Belgrade) for much of the period 289-94 AD


In the passages taken from Panegyric XI (above), the references to Sarmatia were associated with similar references made to Syria or the Saracens:

  1. “... Sarmatia’s devastation and the Saracens subdued by the bonds of captivity ....” (5:4); and

  2. “Those laurels [won by Diocletian] from the conquered nations inhabiting Syria, and from Raetia [above] and Sarmatia ...” (7:1).

Timothy Barnes (referenced below, 1982, p 51) placed the subjugation of the Saracens in  Syria in the summer of 290 AD.  Dodgeon and Lieu (referenced below, at 5.3.1), expanded on the sources for this campaign and suggested (at note 28, p 375) that:

  1. “... Diocletian’s campaign may have been directed against those [Saracens] who were potential allies of the Persians and posed a threat to his plans for the reorganisation of the frontier [in Syria]”.

We learn from Panegyric XI that, prior to the meeting of Diocletian and Maximian in Milan in 290 AD (below):

  1. “Syria had just seen [Diocletian] then Pannonia [on the Danube had] received him”.

Thus we may assume that, after this campaign, he returned to his residence at Sirmium prior to his departure for the meeting at Milan.

Diocletian and Maximian (290 AD)

In Panegyric XI (above), the panegyrist made:

  1. “... a well-meant complaint .... On the very days of the winter solstice, [i.e. in the savage winter of 290/1 AD, Maximian had made the dangerous journey] through  .... the Alpine mountains with which Nature has fortified Italy ...” (2:4).

His destination had been Milan, where he met once more with Diocletian, who had made a similarly difficult journey across the Alps from Sirmium:

  1. “It was a kind of divine flight by which  [Maximian and Diocletian] came suddenly to the same place from the opposite boundaries of the sun ...” (8:3).

The panegyrist went on to describe what had obviously been a formal adventus, which had been held “at the palace at Milan”. 

The panegyrist summarised the Dyarchs’ major military achievements by that time and the harmonious spirit in which they had shared these triumphs:

  1. “ .... each [Augustus] enjoys both his own command and his colleague’s:

  2. -those laurels [won by Diocletian] from:

  3. the conquered nations inhabiting Syria;

  4. ... from Raetia; and

  5. [from] Sarmatia;

  6. made you, Maximian, celebrate a triumph in pious joy; and

  7. -by the same token:

  8. the destruction here of the Chaibones and Eruli;

  9. ... the victories across the Rhine; and

  10. the wars with the pirates [who infested the English Channel and] who were suppressed when the Franks were subdued;

  11. made Diocletian share in your vows.

  12. The immortal gods cannot divide favours between you: whatever is offered to one or the other belongs to both” (6:7 - 7:3).

It is odd that the panegyrist should refer to a victory of Maximian against the pirates, given that this had been achieved largely by Carausius (above).  Indeed, the main purposes of this meeting, like that of the previous meeting in 288 AD (above), must have been to make plans for his destruction.   An indication of this came towards the end of the speech, when the panegyrist proclaimed that:

  1. “The ... stars ... promise you [Maximian] ... a naval victory ....” (19:5).

However, as noted above, he was silent about the fate of the fleet that had been built in the winter of 288-9 AD, presumably because it had failed to meet its objectives.  As we shall see below, the promised future naval victory was still some years away.

Carausius (289-2 AD)


It seems that, following the failure of Maximian’s naval expedition of 289 AD, Carausius had been able to take or to re-establish a presence along the coast of north west Gaul, thereby securing his complete control of the Channel.  Maximian would have faced even greater difficulties had he attempted another naval expedition, so the confrontation had subsided into stand-off.

Carausius claimed that this inactivity resulted from a formal peace, minting coins in Britain that carried the reverse legend ‘PAX AVGGG’ (peace of the three Augusti).  Aurelius Victor suggested that Carausius had been:

  1. “... allowed [by Diocletian ??] to retain his sovereignty over [Britain] after he had been judged quite competent to command and defend its inhabitants against warlike tribes” (‘De Caesaribus’, 39: 39).

However, there is no evidence that a formal peace was ever agreed, and the legitimate Augusti never minted for Carausius. 

Caruasius ‘PAX AVGGG’ issues culminated in one of coins with the obverse of which depicted all three Augusti, described as:

CARAVSIVS ET FRATRES SVI (Carausius and his brothers).

David Sear (referenced below) catalogued eight of these coins (at pp 218-9), which he dated to 292-3 AD.  Diocletian’s response was soon to follow: as described on the following page, the imperial college was soon to be extended and one of its new members, the Caesar Constantius, was to be charged with Carausius’ destruction.

Read more:

‘RIC’ - see Webb (1933) below

D. Potter, “Constantine:the Emperor”, (2013) Oxford 

J. Petitt, “The Extension of Imperial Authority Under Diocletian and the Tetrarchy, 285-305 CE”, (2012), Thesis (MA) from the University of Central Florida, Orlando

T. Barnes, “Constantine: Dynasty, Religion and Power in the Later Roman Empire”, (2011) Chichester

D. Sear, “Roman Coins and Their Values”, (Volume IV, 2011), London

P. Kovács, “Sarmatian Campaigns During the First Tetrarchy”, Anodos: Studies of the Ancient World, 10 (2010) 143-54

H. Gračanin, “The Role of Illyricum in the Tetrarchic Wars”, in

  1. N. Cambi et al. (Eds), “Diocletian, Tetrarchy and Diocletian's Palace on the 1700th Anniversary of Existence: Proceedings of the International Conference held in Split from September 18th to 22nd 2005”, (2009) Split, pp 597-607

P. Porena, “Le Origini della Prefettura del Pretorio Tardoantica”, (2003) Rome

C. E. V. Nixon and B. S. Rodgers, “In Praise of Later Roman Emperors: The Panegyrici Latini”, (1994) Berkeley 

P. J. Casey, “The British Usurpers: Carausius and Allectus”, (1994)  New Haven

M. Dodgeon and S.  N. C. Lieu (Eds), “The Roman Eastern Frontier and the Persian Wars (226-363 AD): A Documentary History”, (1991, reprinted 2002) London

S. Williams, “Diocletian and the Roman Recovery”, (1985, second edition 1997) London 

T. Barnes, “New Empire of Diocletian and Constantine”, (1982) Harvard 

T. Barnes, “Constantine and Eusebius”, (1981) Harvard

R. E. Smith, “The Regnal and Tribunician Dates of Maximianus Herculius”, Latomus 31:4 (1972) 1058-71

P. Webb, “The Roman Imperial Coinage: Volume 5:2”, (1933) London


Diocletian (284-305 AD)

Diocletian's Rise to Power (284-5 AD)      Diocletian and Maximian (285-93 AD)

First Tetrarchy (293-305 AD)      Diocletian, Maximian and Rome (285-305 AD)

Military Campaigns: Maximian and Constantius  in the West (293-305 AD)

Military Campaigns: Diocletian and Galerius in the East  (293-305 AD)

Imperial Cult (285-305 AD)

Diocletian to Constantine (285-337 AD): Literary Sources

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