Bust from a standing figure of Constantine (early 4th century AD)

Musei Capitolini (Palazzo dei Conservatori)

Political Alliances

Lactantius described the web of intrigue that he believed governed the relationships between the four contenders for power following Galerius’ death in April/May 311 AD:

1. “When [Maximinus] heard that [Constantia, the half- sister] of Constantine, was betrothed to Licinius, he apprehended that [Constantine and Licinius] ... meant to league against him; so he privily sent ambassadors to Rome, desiring a friendly alliance with Maxentius ...  The ambassadors were received courteously, friendship established, and in token of it the effigies of Maxentius and [Maximinus] were placed together in public view.  Maxentius willingly embraced this, as if it had been an aid from heaven; for he had already declared war against Constantine, as if to revenge the death of his father Maximian” (‘De Mortibus Persecutorum’, 43: 3-4).
   

As discussed in the page on Maximinus, Senior Augustus (311-2 AD):

1. ✴it is highly likely that Constantine and Licinius had indeed formed an alliance that was cemented by the betrothal of Licinius and Constantia in 311 AD; but
   

2. ✴the existence of an alliance between Maxentius and Maximian is most unlikely, given:
   

3. -Maxentius’ rejection of Maximinus as Consul from September 312 AD; and
   

4. -the implied insult to Maximinus that was inherent in Maxentius’ dynastic coin series.
   

The key point here is that Maxentius had waited:

1. ✴almost a year after the death of his father before consecrating him; and
   

2. ✴about four months after Maximinus succeeded Galerius before rejecting Maximinus’ designation as Consul.
   

Both of these acts of subversion occurred in or about September 311 AD, and both must surely have been triggered by Maxentius’ realisation that he would never be accepted into the ‘legitimate’ imperial college. 

David Potter (referenced below, 2013, at p 135) suggested that the terms of the alliance between Constantine and Licinius:

1. “... insofar as they can be reconstructed from later events, seem to have involved:
   

2. -some sort of military demonstration by Licinius that would tie down some of Maxentius’ forces in northeastern Italy; followed by
   

3. -a pledge of support from Constantine during what would be Licinius’ subsequent war against Maximinus”.
   

Mats Cullhed, referenced below, at p 83) was of a similarly of the view:

1. “[An] alliance was sealed by the betrothal of Licinius to [Constantia] .... and it seems probable that the two Emperors, from the outset, agreed on a joint policy for the future division of the Empire between them, Constantine taking the western part and Licinius the eastern.  When Constantine invaded Italy in 312 AD, he occupied territory that Licinius had claimed for the preceding four years.  Yet this brought about no hostile reaction from Licinius, and their meeting at Milan in February 313 AD [during which the betrothal became a marriage] was held without any preliminary movements on either side.”
   

Maxentius’ Consecration Coins (311 AD)

Sabine MacCormack (referenced below, at p 112) described the minting of this series of coins as:

1. “... the perfect numismatic example ...  of how the idea of consecratio could be used as a propaganda weapon, as a claim for legitimacy”.
   

The series included coins that proclaimed Maxentius as:

1. ✴IMP MAXENTIUS DIVO MAXIMIANO PATRI (to the divine Maximian, father of the Emperor Maxentius) - RIC VI: Rome 243, 244 and 251; and Ostia 25 and 26;
   

2. ✴IMP MAXENTIUS DIVO MAXIMIANO SOCERO (to the divine Galerius, father-in-law of the Emperor Maxentius) - RIC VI: Rome 247, 248, 254 and 255; and Ostia 30 and 31;
   

3. ✴IMP MAXENTIUS DIVO CONSTANTIO COGN (to the divine Constantius, kinsman of the Emperor Maxentius: cognatus, as here, usually meant blood relative: other coins from Ostia used the more accurate adfinis, relative by marriage) - RIC VI: Rome 245 and 252; and Ostia 27, 28 and 29; and
   

4. ✴IMP MAXENTIUS DIVO ROMULO N V FILIO (to the divine and most noble Romulus, son of the Emperor Maxentius)) - RIC VI: Rome 249 and 256; and Ostia 32 and 33.
   

I hypothesised in the page on Maxentius in Rome: (311-2 AD) that this series was associated with three formal consecration processes that Maxentius had staged in Rome with the approval of the Senater: for Galerius; for Maximian; and (somewhat belatedly) for Constantius.

Maxentius’ consecration of Maximian must have seriously offended Constantine:

1. ✴Maximian had betrayed Constantine by subverting a significant part of his army in 310 AD, an act that had prompted Constantine to execute him (or, alternatively, to force his suicide). 
   

2. ✴Maxentius’ consecration of Maximian constituted an exoneration (or perhaps denial) of Maximian’s treachery and a condemnation of Constantine’s action.
   

Constantine’s first reaction might well have been to damn Maximian’s memory.  A number of early sources record that he did so, and Lactantius placed this event in the aftermath of Galerius’ death:

1. “At this time, by command of Constantine, the statues of Maximian Herculius were thrown down, and his portraits removed; and, as the two old Emperors [Diocletian and Maximian] were generally delineated in one piece, the portraits of both were removed at the same time. Thus Diocletian lived to see a disgrace which no former Emperor had ever seen, and ... he [consequently] resolved to die. ... So he, who for 20 years was the most prosperous of Emperors ... became incapable of receiving nourishment and, worn out with anguish of mind, expired.” (‘De Mortibus Persecutorum’, 42).   
   

Since Diocletian probably died in December 311 AD (as discussed in the page on Diocletian (died 311 AD ?)), Constantine’s damnation of Maximian’s memory probably occurred in the latter part of that year. 

Maxentius’ consecration of Maximian also had military implications, since it constituted an invitation to those soldiers in the armies of both Constantine and Licinius who remained loyal to Maximian to defect to Maxentius.  This could well explain why Lactantius considered that Maxentius had:

1. “... declared war against Constantine, as if to revenge the death of his father Maximian” (‘De Mortibus Persecutorum’, 43: 4).
   

Indeed, it seems likely that:

1. ✴Maxentius’ consecration of Maximian; and
   

2. ✴the formation of the alliance between Constantine and Licinius;
   

were connected, albeit that the direction of causality is difficult to determine. 

Maxentius putative putative consecration of divus Constantius (evidenced by his first coins minted for divus Constantius at Rome) would have been particularly offensive to Constantine:

1. ✴according to Zosimus, Maxentius was apt to claim that Constantine was the “son of a harlot” (‘Historia Nova’, 2:9) and hence ‘only’ the illegitimate son of Constantius;
   

2. ✴by officiating at Constantius’ formal consecration in Rome, Maxentius  now claimed him for his own dynasty.
   

This second insult probably made war between Constantine and Maxentius inevitable. 

Constantine’s Invasion (312 AD)

Our knowledge of Constantine’s invasion of Italy in 312 AD  is largely derived from a panegyric (Panegyric XII,  translated into English in Nixon and Rodgers, referenced below) that was delivered at Constantine’s court, probably at Trier shortly after the victory.   The first point that the panegyrist made is that Constantine acted unilaterally and decisively to bring Maxentius’ six-year reign to an end and to recover Rome for the Empire:

1. “... you [Constantine] were the first to embark on a war [against Maxentius] .... when all your associates in imperial power were inactive and hesitating” (2:3).
   

Of course, the panegyrist failed to mention what seems to have been Constantine’s prior agreement with Licinius (above).

The panegyrist also relates that Constantine left the greater part of his army in Gaul:

1. “With scarcely a fourth part of your army, you traversed the Alps against 100,000 enemies in arms” (3:3).
   

The panegyrist noted that Constantine had had to leave part of his army to protect the Rhine frontier:

1. “You left the Rhine secure with armies stationed along the whole border,  ... [favouring] our security rather than the war that you were undertaking” (2:6).
   

However, he touched on another reason for Constantine’s use of only a select body of men:

1. “Severus had led a great army [against Rome in 307 AD], and when abandoned through treachery, he armed his own enemy [i.e. much of this army defected because it was inherently loyal to Maximian]; afterwards [Galerius had brought in a greater force but, weakened by [similar] desertions, had been fortunate to escape” (3:4).
   

The implication was that the loyalty of Constantine’s invasion force was more important than its size.  Unfortunately, a substantial part of his army had supported Maximian in his rebellion of 310 AD and, as noted above, Maxentius had subsequently honoured Maximian by consecration.  We can reasonably assume that Constantine had chosen men for the invasion force who would have been unswayed by this consideration.

The putative alliance between Constantine and Licinius discussed above probably explains why, when Constantine entered Italy from the northwest:

1. ✴Maxentius’ army was deployed to defend against an expected attack by Licinius from the northeast; while
   

2. ✴Licinius, in the event, sat on his hands. 
   

Thus, although Constantine lacked numbers, he had both surprise and mobility on his side.  He rapidly took the garrison city of Susa (modern Segusa) and then defeated a contingent of Maxentius’ cavalry outside the walls of Turin.  He marched on to Milan, which seems to have opened its gates.  The panegyrist summarised the progress so far:

1. “You had captured walls by force [at Susa], you had conquered in open battle [outside Turin]who seemed to be so mad that he would dare either to endure a siege or to fight, especially when, by remaining for some days at Milan, you had given them all time to consult their own best interests ... But that miserable town, Verona ... was held by a large enemy army, with ferocious commanders and the most stubborn of [praetorian] prefects, ....  Pompeianus ...” (7:8 - 8: 1)
   

Maxentius’s Praetorian Prefect, who is named as ‘Pompeianus’  here, is alternatively ‘named Ruricius’ in a later panegyric (Panegyric IV, translated into English in Nixon and Rodgers, referenced below, at 25:4).  He is thus usually referred to as Ruricius Pompeianus. 

Pompeianus, who seems to have judged that he was about to be contained in Verona, managed to escape before the city was completely surrounded.

1. “That wretched man [Pompeianus] was to lead back a greater army to perish with more companions in his destruction.  ... you [Constantine] preferred to engage him with lesser forces upon his return than to interrupt the siege ...” (8: 3-4).
   

Thus it seems that Constantine was able to take some of his besieging army in order to destroy the reinforcing army before it could reach the stricken city.  Constantine seems to have participated in person in this battle, in which Pompeianus was killed and his army routed.  The besieged army at Verona capitulated and the city of Aquileia surrendered to Constantine without a fight.

Constantine then ordered that the captured soldiers from Maxentius’ army should be:

1. “.... seized and shackled, .... lest they scatter .... and [thus did not] merit being preserved a second time ... But from what source were so many fetters to come, which could restrain the hands of so [many] soldiers recently armed?  [To the consternation of his own soldiers, Constantine] commanded that double shackles for their hands [should] be made out of their [own] swords” (11:2-4).
   

Maxentius’ army was famed for its loyalty.  Constantine had no intention of allowing any survivors either to subvert his own men or to escape and rejoin their colleagues at Rome.

After the fall of Verona, Constantine seems to have marched unopposed along the Via Flaminia, arriving outside Rome on 27th October 312 AD.  Lactantius drew attention to the significance of the date:

1. “The anniversary of the reign of Maxentius approached, that is, the sixth of the kalends of November, and the [sixth] year of his reign was drawing to an end” De Mortibus Persecutorum’, 44:4).
   

The stage was now set for the battle of the Milvian Bridge (described in my page on the Battle of the Milvian Bridge), which led to Maxentius defeat and death.