Constantine in Rome (312-3 AD)

The victorious Constantine entered Rome on 28th October 312 AD.  His first meeting with the Senate would be crucial.  According to Eusebius of Caesarea:

1. “Immediately all the members of the Senate and the other most celebrated men, with the whole Roman people ... received [Constantine] as their deliverer, their saviour, and their benefactor ....” (“Historia Ecclesiastica” 9:9:9-11). 
   

A panegyric (Panegyric XII, translated into English in Nixon and Rodgers, referenced below) that was delivered in Trier in 313 AD touched on Constantine’s largesse towards the Senate:

1. “.... you [Constantine]: restored to the Senate its former authority; refrained from boasting of the salvation that [its members] had received through you; and promised that its memory would rest eternally in your breast” (20:1).
   

Constantine’s victory transformed his standing in the Empire: according to Eusebius:

1. “Immediately all the members of the Senate and the other most celebrated men, with the whole Roman people ... received [Constantine] as their deliverer, their saviour, and their benefactor ....” (“Historia Ecclesiastica” 9:9:9-11).
   

In return, according to Lactantius:

1. “This destructive war being ended, Constantine was acknowledged as primi nominis titulum decrevit [the most senior of the three surviving Augusti] .... by the Senate and people of Rome” (‘De Mortibus Persecutorum’, 44.10-11).
   

Constantine was now in sole charge of the western part of the Empire, leaving Licinius and Maximinus to fight for control in the east.

This was a huge blow to Maximinus: Constantine had used the authority of the Senate to reinforce his claim to be at the head of the imperial college.  Lactantius imagined Maximinus reaction to Constantine’s assumption of this title:

1. “... which [Maximinus] had always arrogated to himself.  [Maximinus], when he heard that Constantine was victorious and Rome freed, expressed as much sorrow as if he himself had been vanquished; but afterwards, when he heard of the decree of the Senate, he became outraged, avowing enmity towards Constantine and making his title of ‘imperatorem maximum ’ a theme of abuse and raillery”.
   

Immediately after his designation by the Senate, Constantine (as he was now entitled to do) appointed Consuls for the year 313 AD.  He chose himself and Maximinus.  In accepting this designation, Maximinus seems to have acknowledged that he had been outmaneuvered.

After his formal entry into the city, Constantine embarked on a programme of vilification of the ‘tyrant’ Maxentius, whose head he had paraded on a spike. 

1. “[After Constantine’s subsequent victory], the head of the tyrant [Maxentius] was sent to appease Africa, that after his destruction, [Maxentius] might give satisfaction to that place which he had afflicted while he lived” (Panegyric IV, 32:6).
   

He also disbanded what remained of Maxentius’ Praetorian Guard, posting to the frontiers those of its soldiers who had survived the battle. 

In sharp contrast to his lenient treatment of the Senate, Constantine was extraordinarily harsh in his treatment of Maxentius’ military supporters.  This was articulated by Oliver Hekster (referenced below):

1. “As for the military, the units that were fundamental as a base of power to Maxentius were those that were intrinsically connected to the city of Rome, such as the Praetorian Guard and the Equites Singulares [traditionally and respectively, the personal bodyguard and cavalry of the Emperors].  These groups [had] helped Maxentius to come to power and stayed loyal to him until the bitter end. .... That bond would eventually lead to [their] abolition ... by Constantine.”
   

Such, in this case, were the wages of loyalty.

Demise of Maximinus (312-3 AD)

[In construction]

Constantine and Licinius met at Mediolanum (Milan) early in 313 AD.

Licinius married Constantine's sister Constantia.

It was agreed that Licinius would return property to the Christian church which had been confiscated in the eastern provinces.

Constantine ordered Maximinus to cease his repression of the Christians.

Licinius defeated Maximinus later in 313 AD.  Maximinus was able to escape and reach Tarsus, where he died (perhaps by suicide) in August 313 AD.

Lactantius recorded the fate his children: 

1. “Licinius ... put to death Maximus, the son of [Maximinus], a boy eight years old, and also a daughter of [Maximinus], who was seven years old and had been betrothed to Candidianus [Galerius’ illegitimate son]” (‘De Mortibus Persecutorum’, 50: 6).
   

Thus, his two children had both been born in the period 305-7 AD.   It is difficult to see what Maximinus could have gained from agreeing to his daughter’s betrothal the Candidianus once Galerius had died in 311 AD.  Thus, we must assume that it happened before that, when she would have been less than four years old: Candidianus (who was some 10 years her senior).

Licinius (313-24 AD)

Constantine and Licinius (the last two men standing) now divided the empire between them:

1. ✴Constantine was now the undisputed Augustus in the west; and
   

2. ✴Licinius was now his opposite number in the east.
   

Albeit that he was Constantine’s brother-in-law, he was still in danger from Constantine’s ambition for sole rule. 

Constantine appointed his brother-in-law Bassianus as Caesar for Italy and the Danubian provinces.  Licinius regarded Bassianus as a puppet of Constantine and particularly resented his authority in the Danubian provinces.  Licinius persuaded Bassianus to revolt against Constantine in ca. 315 AD, but the revolt failed.  Constantine defeated Licinius at Cibalae in Pannonia in July/ August 316 AD.  Another battle soon after at Campus Ardiensis in Thrace was inconclusive.

Constantine and Licinius signed a treaty on 1 March 317AD.  Licinius surrendered the Danubian and Balkan provinces, with the exception of Thrace, but retained  sovereignty over his remaining eastern territories.  The final part of this agreement, which was reached at Serdica, saw the creation of three new Caesars:

1. ✴Crispus and Constantine II, two of the sons of Constantine; and
   

2. ✴Licinius the Younger, the infant son of Licinius and Constantia.
   

Caesars Crispus and Constantine Junior

RIC VII Siscia 26 (317 AD)

IMP CONSTANTINVS P F AVG/ CRISPVS ET CONSTANTINVS IVN NOBB CAESS

Johannes Wienand (referenced below, at p. 225) pointed out that :

1. “[Constantine] decided surprisingly late to share power with members of his own family.  Not until 1st March 317 AD, almost 11 years into his reign, did [he] elevate his two oldest sons ... to the rank of Caesar.”
   

The two sons in question were:

1. -Crispus, who was probably about 20 years old; and
   

2. -Constantinus junior, who was only a baby, despite that fact that he was portrayed as a young man on the coinage of the period.
   

Wienand (at p. 226) touched on the likely reason for Constantine’s delay :

1. “[Earlier in his reign], Constantine [had] focused primarily on asserting his own status amid the internal wrangling of the declining Tetrarchy, and on realising his own insistent claims of supremacy ... Not until [he had] come within striking distance of seizing sole power  did he begin systematically to construct a new dynastic college, clearly tailored to himself.  With the Treaty of Serdica on 1st March 317 AD [after an inconclusive battle in which Constantine had considerably strengthened his position], Constantine and Licinius raised their sons Crispus, Licinius junior, and [Constantine junior] to the rank of Caesar”.
   

Constantine probably had a second reason for waiting until 317 AD in order to elevate his sons: he seems to have been suspicious of the ambitions of Crispus, his son from his first marriage to Minervina (as later events would testify).  However, he now had a long-awaited son, Constantine junior, from his second marriage to Fausta (the daughter of Maximian), who had been born in the previous year.

Defeat of Licinius

Relations between Constantine and Licinius continued to deteriorate.  Licinius began to suppress the Christian church in his east from ca. 320 AD.  In 322 AD, Licinius broke the terms of his agreement with Constantine by appointing himself and his two sons Consuls in the east.  Constantine therefore named his third son Constantius II as Caesar in 323 AD.

Licinius declared war against Constantine in the Spring of 324 AD, when Constantine strayed into his Thracian territory while campaigning against Gothic invaders.  It is possible he did so on purposely in order to provoke a war.  Be that as it may, Licinius took this as the reason to declare war in spring AD 324.

Constantine defeated Licinius at Hadrianopolis and, shortly after,  his fleet won further victories at sea.  Licinius fled across the Bosporus, but Constantine followed and won the decisive battle of Chrysopolis (18 September AD 324).  Licinius was imprisoned and later executed.