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An Alternate History of the Roman Empire: The Triumph 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 seventeen articles this took us to 359. We join the story with the Emperor Constantius finding opposition to him centring around the ambitious Pagan General Julian.

Shapur II on the hunt.

In spring 359 the Emperor launched a purge of embezzling officials in his central treasury at Constantinople and in other Eastern regional treasuries in an effort to weed out the corrupt and incompetent and also to collect more money ahead of his planned summer invasion of Sarmatian lands across the Danube. He had already made a major effort to enroll new farmers to grow crops for the Eastern army’s food-supplies and pay extra taxes across the Balkans in 357-8 by encouraging his vassal German ‘kings’ to supply ambitious families who lacked adequate land to farm in their own territories to the Empire, the plan being to settle them as ‘limitanei’ (frontier troops) in the lower Danube valley and as ordinary farmers further to the S and for each family to supply at least one son to the Roman army. This duly led to up to 40,000 Germans arriving in the East as settlers and soldiers in 358-9 and a long-term boost to agriculture and taxes, though it was not Constantius who benefited due to forthcoming events.

But his purge of the embezzlers led to corrupt Antioch treasury financial official Antoninus defecting to Persia with secrets from Constantius’ military treasury and a large sum of gold, and he encouraged Shapur and bribed his courtiers to invade. The suspicious Constantius feared that sympathetic officials and local military officers who were ‘on the take’ had helped Antonius to flee, and the resulting investigations and sackings led to his new appointees undermining the capable Ursicinus as Eastern commander. The Emperor listened to hints that the brusque and not very deferential Ursicinus was cultivating his troops as a ‘practical man of action’ and ‘champion of honesty’ with a view to a later revolt to seize his throne, and replaced him with the elderly and less capable (but less popular so harmless) Sabinian who duly sacked Ursicinus’ highly capable frontier commanders in Mesopotamia. The Emperor summoned Ursicinus to court, but he was approaching Constantinople and possible execution when he was hurriedly sent back to assist with the defence of Mesopotamia.

Shapur had crossed the frontier and the new commanders there fled sooner than fight and be defeated – they were short of the vital armoured cavalry as Constantius had sent for these men to serve on his Danube expedition which was just leaving the capital for the Sarmatian war. Ursicinus was given a special Imperial commission to oversee the frontier and tried to rally the defences of Nisibis and other towns with inadequate troops. But on the 2nd of July 359 Shapur besieged the vital frontier city of Amida, where the historian Ammianus was among the defenders with two legions of Gallic troops (formerly in Magnentius’ army) while Ursicinus vainly tried to induce his timid commander-in-chief Sabinian to advance to the rescue. Instead, Sabinian dithered and sent for troops from Egypt and for Arab mercenaries to come and harass the besiegers by cutting their communications – which failed due to the Persians having too great numbers of experienced troops to be routed by their Roman ambushers. Sabinian failed to risk a battle.

Shapur’s siege-works were burnt in sallies by the defenders and raids by Ursicinus’ men but in November he took Amida by storm after his men shinned up ladders to a patch of wall where some defenders had been made drunk by his agents in the garrison . Ammianus was among those defenders who escaped to the Euphrates, and Constantius had to declare war and end his Sarmatian campaign. The Emperor had led a highly competent if uninspired ‘text-book’ advance to the Dniester to encircle and force a treaty out of the latest boastfully anti-Roman warlord with the help of an army shipped to the mouth of the Dnieper and hired Alan mercenary horsemen brought in from the lower Don, but now he stood accused of neglecting the more vital Persian frontier and too late agreed to sack Sabinian and re-structure his Eastern command as Ursicinus advised. He planned a major campaign in Mesopotamia, and recalled Julian’s friend and general Sallust from the Rhine to command it as he would not give Ursicinus the supreme command out of parnaoia.

That year also saw Constantius organize a Church Council for the West at Rimini and for the East at Seleucia (South East Anatolia), to uphold the new compromise doctrine which he had had formulated to enable the Arians to enter the Church and take its appointments along with the Catholics, and as usual required all the bishops present or absent to sign up to its decrees and then started sacking those who had refused. Bishop Valens of Mursa secured a major triumph for his version of the Creed at Rimini, and Bishop/ Patriarch Eudoxius of Constantinople and Patriarch George of Alexandria did so for him in the East. This seemed to settle the matter of doctrine and Church unity for the Emperor and he planned to drive the ‘minority’ of hard-line Catholic opposition out of the Church into obscurity and hoped that they would duly fade away into a declining, resource-starved minority like the Donatists were doing in North Africa.

(In OTL the Persian attacks penetrated further and sooner – as Constantine ‘the Great’ had not attacked Persia in 337 as he did in this version which weakened their army.)

Early in 360 Constantius issued orders for many of Julian’s troops in Gaul to march East to join his Persian war, reducing Julian’s military strength - which was also useful in case the popular ‘Caesar’ turned disloyal, as his toadies were warning him. Julian sent his general Lupicinus to lead a campaign in northern Britain after raids by the ‘Picts’ (i.e. the Caledonian tribes) as far as Hadrian’s Wall and the first and rather worrying outbreak of seaborne Irish raiders attacking the western coasts of Ordovicia (Gwynedd) and Carvetia (the Lake District) that spring. Constantius held a Church council at Constantinople , centring on the dedication of the completed cathedral of Hagia Sophia by his new Bishop/ Patriarch Eudoxus, a moderate Arian who he had had transferred from the see of Antioch. This issued a revised creed stating that “the son is like the Father”, taking the Arian line, and despite the broad nature of statement in deliberate ambiguity assorted orthodox bishops resisted across the East and depositions follow. This fed into alienation from the Emperor and accusations that he was a ‘heretic’ , which were rallied by inflammatory sermons in exile in Sicily by Athanasius which were circulated by orthodox enthusiasts across the East and revived his supporters in Egypt into a new round of urban riots. The Praefect of Alexandria tried to put them down by force but had had to send his best troops off to Mesopotamia so the undaunted crowds continued rioting and he had to pull his men back and promise toleration for all sects in the city to avoid being overwhelmed, and Patriarch George was besieged by the orthodox in his cathedral until he let the local orthodox return to their main churches and denounced the recent Church Council’s decisions.

Félix Thorigny's 19th century depiction of Julian being proclaimed Emperor in Paris

But now the Emperor’s failings finally touched off a major revolt as the Gallic troops assembling at HQ in Paris to be sent to the East refused Constantius’ orders to march East and shouted that this would leave the Rhine exposed to more invasions by treacherous Germans. At a rowdy rally at their parade-ground on 18 June 360 they declared Julian ‘Augustus’ and raised him on a shield, claiming that he was needed as full Emperor of the West to save the region from Consantius’ tyranny and misrule. It is unclear if he or, more likely, some of his senior officers had planned the demonstration, but he accepted their offer and moved quickly to secure control of Gaul and the Rhine. The regional Praetorian Praefect Florentius, having retired to Vienne as Julian’s troops were about to mutiny so he did not get involved, fled to Constantius and accused Julian of a deliberate plot and treason. Julian sent his envoys Pentaclius and Eutherius to Constantius to assure his peaceful intentions and willingness to restrict his rule to the West, but prepared for a campaign.

Constantius received the envoys at Caesarea-in-Cappadocia where he was heading East for Syria with his main army, having appointed his ‘trusty’ Agila not Ursicinus as his main Eastern commander as he was supposedly more loyal and so caused simmering discontent and threats of mutiny in Mesopotamia. He sent his representative Leonas to Gaul to order Julian to be content with the rank of ‘Caesar’ in return for which he would be pardoned and allowed to rule Gaul, Britain and the Rhineland. Leonas was jeered at by Julian’s troops at their current base at Lugdunum as he announced the offer and was sent back empty-handed, but Julian accepted Constantius’ appointment of Nebridius as his new Praetorian Praefect. In November Julian held his “quinquennial” Games at Vienne on the Rhône, as his generals took over Rhaetia and the administrations in Spain and Mauretania declared for him as a juster and ‘safer’ ruler than his paranoid cousin. In the East, Constantius arrived in Syria and was able to secure most of Mesopotamia as the main Persian army withdrew, but his generals failed in a siege of Amida so it was clear that this would have to be done in 361 and so the planned march down the Euphrates on Ctesiphon would be held up – and sensible generals urged the fulminating Emperor to accept Julian as his fellow-‘Augustus’ , not least as the Empress Eusebia died in early 361 and this left Constantius with only one child, his daughter Constantia (born 350). He quickly married again, to local ‘ex-pat’ Italian heiress Faustina from a major civil service dynasty in Antioch, and declared his intention to finish off the Persians in 361 and then tackle Julian in 362; some of his more trusty, but disliked and not too inspiring, generals were sent West to secure Mediolanum and block the Alpine passes. .

Julian appointed his moderate Catholic supporter Germanianus, a leading southern Gallic bureaucrat of noble birth sidelined by Constantius for supporting Magnentius in 350-2 and recalled by himself in 355 to head his private office, to succeed Nebridius as Praetorian Praefect, the general Sallustius to command in Gaul, the half-Frankish ‘self-made’ officer Nevitta as ‘Magister Equitum’ (Master of the Horse i.e. cavalry), the Italian palace legal official and former Rhine army officer Jovius as ‘quaestor’, the ‘self-made’ Illyrian general Dagalaiphus in charge of household troops (‘Scolae’), and Mamertinus as treasurer. He sent troops under Jovius and Jovinus via the Alps to secure Northern Italy before Constantius’ allies reached the region, and Mediolanum quickly surrendered as they approached – probably due to long-term fears by the palace bureaucrats and local courtiers and nobles alike of Constantius II as a man prone to listen to spies and informers and pursue grudges.

Notably there was no local support by even the most loyal Constantinian dynastic supporter nobles for the Eastern ruler in Gaul, Spain or Britain and very little in Cisalpine Gaul, in which the 353-4 purges seem to have been crucial, and the Catholic majority of bishops backed Julian as preferable to an Arian; so did Pope Liberius and the Senate and days after Mediolanum had surrendered a delegation of officers and cavalry sent by sea from Massilia which had arrived in stia were invited to enter Rome by the Senate. Italy deserted the Eastern ruler in a swift succession of declarations of Julian as ‘Augustus’ amidst popular rejoicing, and some of the ex-ruler’s toadies and informers in the region who had fled were rounded up by defecting officers or Julian’s own men and executed before they could be spared for trial as Julian declared that he preferred to back due legal process. He marched through the Black Forest to the upper Danube in a surprise move while the remaining Constantinian commanders in Italy and Rhaetia, minus most of their men who had defected, were expecting him to attack via Cisalpine Gaul and were fortifying a defence-line near Aquileia. They were taken in the rear and fled and Marcomannia and Dacia defected too; Julian reached Sirmium quickly to force Constantius’ commander Lucilianus to surrender. He sent a speech denouncing Constantius as a tyrant to be read to the Senate, and promised full toleration for all Christian and non- Christian sects plus a free Church Council to determine Christian doctrine by majority vote which the Catholics duly anticipated would be run by themselves as they would have a majority in it once Julian’s promises to remove all ‘illegally appointed’ bishops (which in practice meant Constantius’ recent Arian proteges) were fulfilled. The pagan priesthoods and their allied traditionalist nobility in Rome were particularly supportive to Julian, partly due to his public statements of toleration as ‘Caesar’ and partly due to ‘tip-offs’ from young Italian pagan nobles who had been educated with him at Athens and shared his philosophic enthusiasms.

Praetorian Praefect Taurus refused Julian’s offer of an amnesty and fled Italy; Julian advanced South East to Naissus (Nis) and sent Constantius’ regiments stationed at Sirmium, who deserted to him but were not trustable, out of the way to Gaul and the upper Rhine, carefully broken up into small detachments and due to be dispersed among his own loyal legions. Some of them mutinied en route and seize Aquileia so he ordered Jovinus to deal with them, which he did. Constantius, refusing to back away from the Arians to win Catholic support in the East, replaced the popular but orthodox Miletius as Bishop/ Patriarch of Antioch with the more Arian Euzoius on the appeal of his own close supporter Eudoxus of Constantinople; Miletius and his rival Paulinus then quarrelled over the leadership of the Antiochene orthodox but both factions outnumbered the local Arians. Constantius set out for Constantinople and sent ‘Magister Peditum’ (Master of Infantry) Arbetio ahead and Godoamarius to secure the Balkan passes, but fell ill en route as Julian’s advance-guard under Nevitta reached the Balkan passes first and blocked them to his troops.

On 3rd of November 361 Constantius died at Mopsucrene in Cilicia, aged 47, and his generals abandon the ministers’ plans for election of successor and sent officers Theolaiphus and Abigild to Julian to accept him as Emperor; on the news Constantius’ troops at Aquileia surrendered. A capable but paranoid and too inflexible ruler who threw away much goodwill by listening to schemers and flatterers, Constantius had proved an object lesson on how to be a competent ruler who still did not achieve his potential and showed the way how not to rule the Empire – as Julian, who had respect for his sense of duty and overall devotion to the Empire but not for his choice of advisers pointed out in his obituary speech when he reached Constantinople.

Julian recalled all exiled orthodox Bishops, and sent his uncle (his mother’s brother) Count Julian to Antioch as “Count of the East” to secure provinces. He entered Constantinople in triumph, buried Constantius beside his father Constantine at the Church of the Holy Apostles, and pardoned Constantius’ officers. Bishop/ Patriarch George of Alexandria was now abandoned by the local Praefect and his troops and lynched by a mob. Athanasius was allowed to return by his congregation’s request to the now sole Emperor and Julian took no action against the assassins but attempted to discourage inter-Christian violence generally with his statements.

In 362 Claudius Mamertinus, a leading orator, and the general Nevitta were consuls. Julian organized a judicial commission at Chalcedon, including generals Jovinus, Arbetio, and Nevitta, to execute Constantius’ favourites including the spymaster Paulus and the chamberlain Eusebius, and his soldiers secured the execution of the unpopular treasurer Ursulus. This was part of a larger purge. Ex-‘Master of Offices’ Palladius was exiled to Britain for undermining Gallus in 354 and his successor Florentius was exiled to a Dalmatian island. Artemius, the thuggish and bribe-taking Arian Praefect of Egypt in 357-61, was executed, and replaced by Ecdicius Olympus.

In terms of new blood that Julian bought in; Anatolicus, Julian’s chief administrator at his army headquarters in the mid-late 350s, became his “Master of Offices” and Felix became finance-minister (“Count of Sacred Largesses”). There was also a religious bent to this change of personal, Julian was after all a notable Pagan taking over from a series of Christian Emperors. Senior Roman pagan noble Salutius Secundus was made Praetorian Praefect of East, though this was balanced by Celsus, a local and moderately Catholic Romnao-Antiochene noble who was the leading pupil of Libanius of Antioch, being made governor of Syria.

(Events largely as in OTL; but in this version Julian’s wife Helena is still alive and the Persian threat is less severe.)


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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