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An Alternate History of the Roman Empire: The Rise of Julian

By Tim Venning

This long Series of Articles discusses a hypothetical history of the Roman Empire wherein Marcus Aurelius lives longer and so it's more stable. In the first sixteen articles this took us to 353. We join the story with the Empire newly united under the rule of Constantius.

Constantius II depicted in the Chronography of 354 dispensing largesse

In the October and November of 353 Constantius held a great Games at Arles to celebrate his ‘Vicennalia’, thirty years having passed since he was made ‘Caesar’. He wintered there and early in 354 held a Church Council of the West at Arles to condemn Athanasius and his rigid orthodoxy and to open a theological formula of compromise to the Arians, bullying the majority of Catholic bishops there into signing. Liberius of Rome refused and demanded a General Council with the Eastern Church. This was ignored and he was threatened with deposition and sent packing. At Valence in the Rhone valley, the Emperor held military manoeuvres and summoned more troops from the middle Danube, Marcomannia and Dacia to prepare for a campaign against Gundobad and Vadomar, kings of the Alemanni, who had crossed the Rhine near Colonia Agrippinensis and invaded Gaul that spring to take advantage of the chaos after the fall of Magnentius.

During the prolonged wait for the new troops to arrive and the war to start, which left the plundered areas of Belgica and adjacent lands around Argentorate exposed to German plunder to the locals’ anger, the troops assembled at the main military headquarters at Chalons started to riot at inadequate provisions. Constantius sent his Praetorian Praefect Rufinus (his cousin and ‘heir’ Gallus’ mother’s brother) to calm them –allegedly he or his ambitious chamberlain Eusebius were quite prepared to see the men lynch Rufinus in case the latter resists their planned destruction of his nephew, who Constantius was hearing alarming reports about. But Rufinus won the men round with a bold but sympathetic speech and a promise of remedies, and Eusebius brought them cartloads of money from the court to secure their goodwill until the Emperor arrived. Once the reinforcements turned up the cautious Constantius was convinced that he could risk fighting, and he advanced to pursue the Alemmani back to the Rhine.

But the Germans evaded a planned Roman trap West of the river near the Moselle valley, and their compatriots in the Roman army were suspected of tipping them off about it. Constantius accepted an offer of peace from the Alemannic leaders in return for them keeping their loot and a treaty was signed; they became Roman allies and vassals, returned their prisoners, and agreed to supply tribute and men to the Roman army each year. With them having left the Empire, Constantius could – exaggeratedly – claim a victory to match those of his father and grandfather and rebuild the Lower Rhine army, enrolling many new recruits and rebuilding burnt or abandoned fortresses as far as the mouth of the river. But the damage to farms and towns across Belgica took longer to repair, and with farmers and as a result food for the army and townsfolk in short supply for a decade or so to come Constantius – and later his nephew Julian as ‘Caesar’ – had to import much of the needed food-supplies from unravaged Britain, boosting its farmers’ income and encouraging the expansion of canny corn-growing landowners’ estates there. This provided a ‘boom’ in the 360s and 370s in villa-building by wealthy farming aristocrats and self-made entrepreneurs throughout Britain apart from the still-Saxon-afflicted Eastern coasts.

Gallus, based at Antioch, was aiming at his own glory at this time to rival his cousin, and in 354 he planned a Persian campaign and drew up plans to goad the ‘Great King’ Shapur into attacking Roman territory so he could have an excuse to invade Mesopotamia and march triumphantly to Ctesiphon. But this was reported to Constantius who had no intention of tackling Persia yet – the restive Sarmatians on the lower Danube were next in his plans – and was furious. Gallus had also become arrogant and unstable, encouraged by flatterers in his entourage, and employed informers to report on malcontents who were killed and had their property seized to fill his treasury and counter his extravagance. He was encouraged in this by his wife, Constantius’ sister and Hannibalianus’ widow Constantina, who was a woman nearly a decade his senior, who the Emperor had made him marry in 351 to keep an eye on him. Moreover, he'd come under the religious influence of the Arian deacon Aetius who Constantius had sent to convert him and see that he did his best to fill the Syrian Church with Arian appointees.

Thalassius, his Praetorian Praefect, did nothing directly to restrain him but, following instructions, reported on his erratic behaviour to Constantius. Later in 354 Gallus, hearing of food-shortages at Antioch, fixed the food-prices to prevent riots that could lead to attacks on himself or reports to his detriment to his cousin. He also handed over Theophilus the governor of Syria, who he disliked for lecturing him on his duties and trying to talk him out of partying all night, to an angry mob that confronted them at the Games and let them lynch him on the spot. He then arrested protesting Antiochene senators who he accused of hoarding food; he was only prevented from executing them as scapegoats by the “Count of Oriens” Honoratus. Constantius sent his new Praetorian Praefect of East Domitian (Thalassius having died inopportunely before the Emperor could tell him to arrest Gallus) to investigate, and the suspicious Gallus arrested him for not paying his respects at the Palace immediately he arrived and ordered him to be killed then had his “Quaestor” (finance-minister) Montius killed as well for trying to stop the execution. Then, Gallus had the governor of Phoenicia, Apollinaris, and his son executed after hearing that someone unknown had commissioned the workers at Imperial robe-factory at Tyre to make a purple Imperial robe; the workers were rounded up and tortured in a vain effort to find out who the would-be ‘rebel’ was but no suspect was identified.


Gallus was clearly an embarrassment to the Emperor and not only was proving vain, vicious, and unstable, and so not a capable future Emperor, but an egomaniac who might well decide to revolt before he was arrested. Constantius had to act, and in summer 354 he lured Gallus to Mediolanum with hints of immanent co-rulership. He also summoned the capable and highly regarded ‘Count of Oriens’ Ursicinus (whose entourage included the future historian Ammianus Marcellinus, a junior officer) in case he took advantage of the vacuum in the East to revolt. Gallus hesitated about his summons but, demoralised by the recent death of his wife, set out from Antioch and held Games at Constantinople en route where Constantius’ envoys Leontius and Lucilian arrived to accompany him West with false assurances. Count Barbatio, Constantius’ nominee, took over Gallus’ bodyguard and escorted them back to Syria to split them up and send most off on frontier-duties; the same happened to most of Gallus’ loyal officers at Antioch.

Gold solidus of Constantius Gallus. Shared under the CC BY-SA 3.0 licence.

At Poetovio in Noricum Barbatio suddenly separated Gallus from his entourage, arrested him for treason to the Emperor, and bundled him into a carriage dressed as a common soldier for speedy removal before anyone could rescue him. He was taken to isolated Pola in Istria, questioned by the chamberlain Eusebius about his many crimes which he blamed on his ambitious wife who he said had been ‘bad-mouthing’ Constantius for killing her previous husband and encouraging Gallus to make himself popular with the troops and Antiochenes ahead of a revolt. He was then beheaded by Imperial police-officer Count Sabinian, aged probably 28. Gallus’ young brother Julian, aged 23, was summoned to Constantius’ court at Mediolanum, interned at Comum (Como) while he and his small entourage were questioned and Constantus checked that he had behaved loyally while studying at Ephesus, and after being cleared of aiding his brother was exiled to Athens under the guise of continuing his studies. He claimed to be interested in learning philosophy and studying Plato and Aristotle not chasing after power, and whether or not Constantius believed him he agreed that the prince was safer out of the public eye and if he was really as intelligent and honest – and as uncorrupted by the lust for power as he and his friends claimed – he would be loyal and also might be a good Emperor.

Julian duly learnt pagan philosophy at Athens avidly. Meanwhile assorted officers and courtiers of Gallus’ were brought to the Emperor’s court for trial after the completion of the investigations at Antioch and were exiled or killed, and Paul ‘the Chain’ and the equally sinister Mercurius, known as the ‘Count of Dreams’ for finding out about people’s ‘treasonable dreams’ in confidence and reporting them, were let loose to find more plotters. Ursicinus was initially sentenced to death as Constantius (encouraged by Eusebius and the general Arbetio) was jealous of his popularity with the Eastern frontier troops, but was reprieved as too good a commander to lose.

In 355 Constantius campaigned against a southern Alemmanic tribe, the Lentienses, near Lake Constance on the upper Rhine. ‘Magister Peditum’ Silvanus, a distinguished officer of Frankish descent who played a vital role in the Mursa campaign, was sent to North East Gaul to drive out German raiders from the Rhine-mouth region; while he was absent his ingenious Court rival Dynamius, superintendent of the Imperial baggage-train, used his signature to forge some letters to supposed fellow-conspirators and presented this to Constantius as evidence of a plot. The general Malarich, who spoke up for Silvanus’ loyalty and offered to collect him so he could prove his innocence, was implicated too, but when ‘Master of Offices’ Florentius headed a commission to investigate the forgery was detected and the ‘plotters’ , including Praetorian Praefect Lampadius, were cleared – without Dynamius’ part being detected.

Silvanus, unaware that he was being cleared, panicked and declared himself Emperor at Colonia Agrippinensis to save himself; the courtiers, fearing he would bring in the Franks (he had a Frankish wife and had earlier bene a successful envoy to them to distribute gifts and collect tribute) to aid a rebellion, reluctantly let Ursicinus, as a popular general who could win back his troops’ loyalty, go to the rebel headquarters carrying Imperial letters that pretended that Constantius is unaware of the revolt and about to promote Silvanus. The rebel received Ursicinus (and his officers, including the historian Ammianus) kindly, and while he was wondering whether to abandon his revolt they won over some of his wavering troops who attacked and butchered their leader; the rest of army returned to its allegiance to Constantius and a major revolt was headed off. The success of the ploy reassured Constantius about Ursinicus and he was promoted and was never doubted thereafter, but the needless loss of competent Silvanus due to a plot by his greedy court rival soon leaked out and damaged the Emperor’s reputation further and it was to aid the readiness of the local troops to aid Julian in revolt five years later.

Julian as portrayed by Giovanni Battista Cavalieri.

In October 355 there was a Church Council of Milan to uphold Arianism and denounce Bishop Athanasius. Constantius deposed and exiled all bishops who refuse to sign the new theological formula in favour of Arianism, including Hilarius of Poitiers, the aged Constantinian veteran Hosius of Cordoba, and Dionysius of Mediolanum; Pope Liberius of Rome was summoned, told to sign and refused, and was exiled to Berroea in Thrace for obduracy and a faction at Rome elected the Imperial ally Felix to replace him but most of the clergy and laity boycotted him. Athanasius was confirmed as ineligible for any bishopric for obdurate ‘heresy’ and insulting the Emperor and was exiled to Libya, and his see at Alexandria was given to the Arian loyalist George – whose arrival there in spring 356 was marked by violent riots and boycotts so that his religious services had to be protected by troops. That autumn of 355 Julian was summoned to Mediolanum as Constantius’ reluctant choice to restore order in Gaul as there were no other Imperial males available and the Emperor feared that nay non-prince who did this might well choose to use his popularity with the troops to revolt. He was granted the rank of “Caesar” and the hand of Constantius’ sister Helena (a decade older than him and the younger sister of the late Constantina, Gallus’ wife, but much less interested in politics) in a formal ceremony on 6 November. On the 1st of December, he left the Court and set out to cross the Alps to Vienne where he received a warm welcome, then wintering in the Rhône valley with his wife.

In 356 Julian cleared the barbarians out of North Eeast Gaul after a major Alemannic incursion across the middle Rhine and little resistance by Roman garrisons who were demoralized by recent sackings of officers suspected of sympathy for Silvanus. On the 24th of June he arrived at Trier, where a recent German attack had been driven off by elderly military veterans as the garrison had fled rather than fight for an unknown and disliked Eastern loyalist appointed to command there by Constantius. He held a council-of-war with the remaining non-purged and competent officers and senior administrators in Belgica who the Emperor had retained (a minority of the pre-350 staff) and reassured them that he would not be killing or exiling all who he or his courtiers disliked or had any greed for their possessions. He raised new troops from the locals at the cost of denuding farms and marched across the countryside of the Moselle valley, defeating German ambushes en route, West to Remi (Reims) to cut off another large band of raiding Germans there.

He joined the capable but locally disliked Eastern new arrival ‘Magister Equitum’ Marcellus, who was commanding in Belgica , defeated the invaders of the province in several expertly-planned battles that showed that despite his lack of military experience he had read all the relevant manuals, and then retook the ransacked Lower Rhine fortresses North of Colonia Agrippinensis. He wintered at Sens. In early 357, as consul with Constantius, he drove off a month-long German siege of Colonia, but was not assisted by the nearby Marcellus who Constantius recalled at his request and who spitefully started spreading rumours at court about Julian’s treasonable ambitions. Constantius’ sister and Julian’s wife, Helena, was visiting the Emperor at the time and persuaded her brother to ignore them. Julian, reinforced by ‘Magister Peditum’ Barbatio and 25,000 troops from Italy, cleared the lower Rhine valley of invaders and sent reinforcements South to relieve Basilia (Basle) which was under attack by a large incursion of Alemanni from the Black Forest.

Barbatio refused to loan him ships to get at Germans who are holding out on islands on the Rhine, possibly hoping for him to be defeated so he could report unfavourably to Constantius and be asked to arrest and replace him, but Julian’s men swam over and evicted them. In summer the Alemanni under kings Chnodomar and Vestralp advanced on Julian’s new base at Argentorate (Strasbourg), confident that he had only 23,000 troops and could be overwhelmed by their superior numbers., But; Julian defeated them in a hard-fought infantry battle with a mixture of ingenious tactics selected from his manuals, earning his men’s (and even Barbatio’s) respect for his calmness while under fire from a hail of German spears, and the Roman archers devastated the poorer-protected Germans ahead of a classic ‘squeeze’ on their large but untidy square formation of warriors by wedges of infantry on either side pressing inwards. The Germans eventually broke and ran, and the fleeing Chnodomar was thrown from his horse as he tried to reach the Rhine, captured, and deported to Italy; Julian reached Moguntiacum and crossed the Rhine on a bridge of boats to raid the Alemanni’s homelands across the Rhine and Main, forcing them to surrender and hand over hostages and tribute and promise to keep the peace. That autumn he defeated Frankish brigands around the lower Moselle valley, and was finally able to declare Roman territory cleared of all invaders for the first time since 351.

(In OTL, the Germans penetrated the eastern Gaul further and there was a more desperate struggle to drive them out due to worse Roman losses in the civil war.)

Meanwhile Constantius had paid a grand State visit to Rome in April 357 to celebrate his Triumph over Magnentius, and donated an Egyptian obelisk to the Circus Maximus; he was noted for his rigid bearing at processions, more like a statue than a human being, but regarded it as appropriate for the Emperor as the chosen one of God and the defender of both the Empire and the correct Christian doctrine. He was lobbied on behalf of Pope Liberius, but did not allow him to return to Rome until 358 and then insisted that he agreed to allow his now deposed Arian rival, Felix, to stay in Rome unmolested and lead a rival Arian congregation who could use one of his churches. The Emperor then left Rome in a hurry as the Germans invaded Rhaetia across the upper Danube, and sent Ursicinus to command at Antioch and Severus as ‘Magister Equitum’ to Trier to back up Julian. That summer he went East to Moesia to fight Sarmatian incursions, and wiped out a rebel tribe, the Limigantes.

In 358, having wintered at Lutetia/Paris as his new ‘rear base’ to recruit extra troops from the young men of well-populated farming districts in western and north-western Gaul where their loss would not affect agriculture so much , Julian marched to the lower Rhine and crossed a bridge of boats to invade the lands of the ‘Salian Franks’, over the river from eastern Belgica and stretching to the Zuyder Zee and the lower Elbe. The British fleet landed an army at the mouth of the Elbe to join local allied chieftains and trap the Franks from the rear, preventing other anti-Roman tribes from joining them. He recovered Roman control of the region and the lower Elbe, enforced their kings’ vassalage and levied an annual tribute of food-supplies, timer and troops from them but gave their chieftains rich gifts too, and so secured the Empire’s lower Rhine frontier to give it time to rebuild its war-denuded fortresses and manpower. He then marched up the Rhine to Colonia and crossed it near Moguntiacum to attack the Alemanni, joined by troops sent from Marcomannia.

The kings of the Alemanni were outnumbered and after finding that retreating into the forests did no good – the ‘Caesar’ marched after them and had roads cut through the woods and wooden forts set up to starve them out – they surrendered and agreed to keep the peace as the Romans occupied their territory. The southern Rhine frontier and Upper Germany was thus secured by September 358 and Julian became hugely popular in the previously-threatened provinces West of the Rhine and respected by his (Constantian loyalist) officers as a ‘winner’ and a brilliant strategist. But at court Julian’s enemies, including those who had brought Gallus down and feared his revenge and those Arians and other Christians who disliked his enthusiasm about ‘blasphemous’ pagan philosophy, continued to jeer at him as a vainglorious and over-praised ‘Hellenophile’ who wore a Greek-philosopher-style straggly beard, lived in ostentatious simplicity, and went on about ancient ethics as a guide to the way to rule Rome in a manner not seen since Marcus Aurelius. Conversely, Julian’s favourable remarks about Rome’s old pagan traditions at his winter courts and his playing up his role as heir to incorruptible and simply-living ancient generals (e.g. Camillus from the 4th Century BC and Scipio Africanus) led to Italian pagan nobles who had visited his court or sent their sons to serve in his army coming in the late 350s to see him as their great hope for the future. The competent and sternly practical Constantius had shown himself as a religious bigot and a tyrant who listened to informers and spies and ruined honest men like Silvanus, and his visit to Rome in 357 had left a poor impression for his arrogance and his treatment of the Senate as his vassals not his partners. Moreover, the split went deeper than just Pagans vs Christians, due to the way that the Emperor lavished money on Felix’s Arian congregation in Rome, the Catholic community there had it in for him too.


Timothy Venning is a respected Historian who won the London University History Prize in 1979 and whose latest straight history book is Cromwell's Failed State. He has also written multiple books of counter factual essays including Caesars of the Bosphorus, Eternal Caesars, King Charles or King Oliver and King Henry IX, all published by Sea Lion Press, and If Rome Hadn't Fallen.


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