Pope Leo the Great (29 September 440 – 10 November 461) was one of the key figures of the Church in the mid-fifth century. Unanimously elected as Pope in 440, Leo became one of the most prominent figures in Rome as well as in Italy, and his position made him a part of the international framework of ecclesiastical politics for twenty-one years, during which he was ‘the major representative of Latin Christianity.’¹ In this article Leo’s changing relationships with the Eastern Empire and the barbarian tribes that penetrated Italy during his pontificate are examined. Together they help us reconstruct Leo’s identity as a pious bishop with political power.

The political and religious character of the position to which Leo rose was in no way definite in the fifth century. The Western imperial court had resided in Ravenna since 402,² but from around 450 onwards the Western emperor moved to Rome once more, showing that Rome’s past importance as the capital of the Roman Empire had not been forgotten by the secular powers.³ More notably Rome excelled in spiritual authority. Leo believed that he was sitting on the cathedra Petri, the chair of St Peter: Rome was the only Western apostolic see, claiming its origins from Sts Peter and Paul. Further the pope exercised ecclesiastical authority over the Western Empire⁴ and East Illyricum, where the bishop of Thessalonica ruled as the vicar of the Roman bishop.⁵ Rome’s elevated position amongst sees was also a part of church tradition: its superior ranking had been acknowledged in Canon 6 at the Council of Nicaea (325), alongside Alexandria and Antioch.⁶ Roman authority was thus based on apostolic connections and the rulings of Church Fathers, as well as on the exercise of legitimate control over Italy, other Western provinces and the subordinate bishopric in Illyricum. Leo had a highly refined understanding of what he conceived the power of the Roman bishop to be – universal and eternal, superior and unaffected by the matters of the world – but his contemporaries did not share this view.

Leo was not necessarily a man of great importance upon accession. In a wider context, he became pope in the middle of the turbulent fifth century during which the Roman Empire collapsed in the West and was transformed into new barbarian kingdoms. Leo discussed contemporary secular affairs in his correspondence only if they were directly relevant to the matter at hand, which they often were not. We must, therefore, put the epistolary evidence into context for him in order to grasp the situation in which his letters were written and what Leo’s motives in writing them were.

As will become apparent, Leo relentlessly emphasised the power of the pope, but there was a gap between his theory of papal primacy and his authority in practice. This led to a clash between Leo and the secular rulers. The epistolary evidence demonstrates Leo’s struggles and ambitions as he actively sought to strengthen his position and prove that the Roman See truly had the special power that he believed it to possess. The challenge, as Leo was to realise, was making this claim believable outside Rome.

The Politico-Religious Sphere in the Fifth Century

In his letter to Bishop Julian of Cos in 453, Leo the Great stated, ‘So long as the Christian rulers act with holy zeal for the faith, the Lord’s priests may confidently pray for their realm.’⁷ Leo thus saw the relationship between spiritual and secular authorities as co-dependent and complimentary, but ecclesiastical support was also conditional. During the past century, the papal office had adopted a practical dimension and had included further secular duties within its realm that Leo was expected to carry out as his predecessors had. As we shall see, Leo’s secular role was most evident when he encountered barbarian leaders. This development in the papal role coincided with secular rulers becoming increasingly further involved in spiritual affairs, and the communication between the representatives of the two spheres became exceedingly crucial.

The integration of church and state had begun in the fourth century, inherently complicating the relationship between religious and secular authorities. Theodosius I (347-95) extensively legislated against heresies and established Christianity as the religion of the empire.⁸ Imperial support was advantageous to the faith as the secular powers could operate in spheres the clergy could not and, by Leo’s time, the Church had begun to rely on the intervention of the public authorities when church disputes turned violent.⁹ It was essential for bishops, especially for major ecclesiastical figures like Leo, to be in contact with the forces that had the power of stabilising and influencing the Church.

Forty-three of Leo’s letters to emperors and empresses have survived, representing roughly a third of his surviving correspondence.¹⁰ The overwhelming majority of Leo’s letters were sent to Constantinople, precisely because of this significant communication with the imperial court. Leo’s geographical distance from the Eastern Emperor made it difficult for Leo to exert his authority in the Eastern court, but at the same time the distance enabled him to exercise power more freely in Italy where the Western Emperor was too weak to control him and the Eastern Emperor was too far removed to impose authority on him.¹¹ The result was a balancing act in which Leo’s authority was always dependent on the imperial forces he was dealing with and on their willingness to co-operate with him. The correspondence exhibits the remarkable way in which Leo utilised changing political circumstances to promote and enforce Roman primacy.

The Conflict between Leo and Theodosius

At Leo’s accession, the Eastern Emperor was Theodosius II (reigned 408-450). The correspondence with the emperor demonstrates the pope’s difficult relationship with an emperor who did not want Leo to interfere in his affairs. Theodosius did not initially exercise power in the East as he became emperor at the age of seven,¹² and neither did Theodosius possess the qualities of an emperor as he did not take up a military role on campaigns, but instead preferred to stay in Constantinople, which had two rather obvious effects. Firstly, the emperor was most influenced by the contact of his own court, and secondly, he was thus less exposed to outside views.¹³ This made it more difficult for Leo to implement his authority in Theodosius’s court.

As Theodosius lacked the image of a strong military leader, he found other ways to strengthen his position: Theodosius identified himself through religion. He did this insofar that his contemporaries perceived the imperial family as a type of monastic establishment in itself.¹⁴ The emperor’s devoutness was directly beneficial to his subjects as his observance of fasting and praying translated to God’s favour and subsequent military successes.¹⁵ As a man dedicated to Christianity, Theodosius expectedly involved himself in religious affairs, but this did not mean that he shared the religious views of the bishops or, in our case, Leo’s.

Theodosius’s focus on imperial piety complicated rather than simplified his relations with the pope. The schism between the Eastern emperor and Rome was the consequence of Theodosius’s independent religious policies, affected by his political alliances. The Eutychian controversy that emerged within the Church in the late 440s was in many ways a follow up of the Nestorian heresy of the early 430s,¹⁶ witnessing Leo and Theodosius taking different sides in the debate. The Eutychian heresy and the Second Council of Ephesus that was called to solve the crisis in 449 had a political nature and proved to be a nightmare for Leo, who labelled the council a latrocinium – a robber council.¹⁷ The council deposed Flavian of Constantinople (446-449), with whom Leo had sided, and restored Eutyches, whom Leo had condemned.¹⁸ In the late 440s eunuch Chrysaphius had considerable power over Theodosius. Chrysaphius was the godson of Eutyches, and it is not at all unlikely that Chrysaphius determined the actions taken by Theodosius at Ephesus II.¹⁹ Constantinopolitan politics were affecting ecclesiastical matters – a factor wholly outside Leo’s sphere of influence.

Leo’s attitude towards Theodosius changed vastly in the aftermath of the council. Before Ephesus II, Leo addressed Theodosius as a great and pious leader,²⁰ as was expected and proper and which was the stylistic norm of the time. However, the strained relations between Leo and Theodosius reached their peak when Leo, appalled by Ephesus II, stated: ‘The point of faith at issue [the Incarnation] is so obvious that it would have been more reasonable to have refrained from summoning a council.’²¹ Leo’s direct and unapologetic articulation of his own, contrasting opinion underlines his dissatisfaction with the emperor and, indeed, is Leo’s boldest statement to any emperor. Theodosius could not have been able to miss the discontentment the bishop of Rome was expressing. Leo was aware that ‘private interests [were] being carried under the cloak of religion,’²² but despite Leo’s clear objection to Ephesus II, Theodosius ignored the wishes and subsequent protests of the bishop of Rome. Leo wanted a new council in Italy and asked Theodosius to call one three separate times.²³ Theodosius refused as he saw Ephesus II as having proven his orthodoxy.²⁴

Leo’s relationship with Theodosius heightens the complexity of emperor-bishop relations as secular politics penetrated the religious sphere. The situation was worsened by the emperor’s confidence in his religious policies and his conviction that Eutyches’s views were not heretical. The symbiosis of church and state took away episcopal autonomy with the result that the voice of Rome could be and was ignored in Constantinople.

Post-Theodosian Emperors

Leo did not consider Theodosius to be the real source of spiritual insight in the East, but instead turned to Pulcheria (399-453), the emperor’s sister and the future empress. Leo’s letters to Theodosius were usually written alongside letters to Pulcheria.²⁵ Pulcheria had played a dominant part in her brother’s childhood and had exercised significant influence over him even after his accession,²⁶ and Leo’s correspondence with her shows the pope’s awareness of this Eastern power dynamic.

Pulcheria added further religious dimensions to the Theodosian dynasty by having taken a public vow of virginity and by connecting herself to the cult of Theotokos, the Mother of God.²⁷ Leo acknowledged her exceptional spirituality: in letters sent to the Eastern imperial court concerning Eutychianism, Pulcheria’s letters included a more detailed account on Eutyches’s doctrinal errors than Theodosius’s.²⁸ Significantly, Pulcheria sided with Leo in the Eutychian heresy,²⁹ and Leo was grateful and relieved for Eastern support, stating that he had ‘more confidence in my request [of measures against heresy] now that I have received the backing of your esteemed encouragement.’³⁰ However, during the crisis, Pulcheria’s influence in Constantinople had waned. Chrysaphius and Theodosius’s wife Eudocia had more power over the emperor than Pulcheria did.³¹ Therefore, while Pulcheria presented an opportunity for Leo to exert his influence in the East, the opportunity was limited by Pulcheria’s decreased power. Neither did Pulcheria’s shared views with Leo translate to her acting according to his wishes. She gladly accepted Roman support, but she was not interested in papal commands if they did not fit her views, seen when, like her brother, Pulcheria turned down Leo’s proposal of a universal Italian council, emphasising that she wanted it in the East.³²

Theodosius’s sudden death in 450 changed the relationship between the Roman bishopric and the Constantinopolitan court. The new emperor Marcian (450-457) married Pulcheria to tie himself to the Theodosian dynasty,³³ and his relationship with the pope was more amiable than that of his predecessor. The Eutychian crisis was solved in the Council of Chalcedon in 451, called together by the new emperor, who sided with his wife and, consequently, Leo.³⁴ The friendship Marcian showed towards Leo also had a political dimension as Leo had significant influence over the Western imperial family, to which Marcian was related to only through his nominal wife.³⁵ Marcian’s religious policies were also shaped by the increased prestige of Alexandria in the aftermath of Ephesus II, threatening the position of Constantinople in the hierarchy of sees.³⁶

Leo and Marcian’s relations soon became more complex, the initial friendship wearing thin when Marcian ignored Leo’s request to postpone the Council of Chalcedon, causing the pope to note that ‘it was our belief that your Clemency could yield to our wishes by ordering that the council of bishops be put off.’³⁷ By this stage, Eastern emperors had repeatedly ignored Leo’s wishes, demonstrating the limited influence Leo had in the Eastern secular sphere. Shared imperial and Roman views on heresy did not elevate the Roman position, but further changes in Constantinople did.

When the confidence of the imperial family in their religious policies waned, Rome grew in importance. While it is an exaggeration to claim that Marcian was ‘a man of little substance’³⁸ as he was one of the leading senatorial figures and had a strong military background,³⁹ it is fair to say that he had not involved himself with religion the way Theodosius or Pulcheria had. After the death of Pulcheria in 453, Marcian lost his connection to the Theodosian dynasty as well as the woman whose religious policy he had followed. Marcian now turned to Leo for assistance in religious matters: he asked Leo to be more favourable towards Anatolius, the bishop of Constantinople,⁴⁰ whom Leo strongly disliked. Leo’s consent or favour was not essential, as Theodosius had shown, but Marcian needed Leo’s support more than his predecessor had. Marcian had to prove himself as a capable emperor, which most likely influenced his decision not to postpone holding a synod in 451.⁴¹ Marcian also approached the pope in the matter of Eudocia, Theodosius’s widow now residing in Jerusalem, who supported the anti-Chalcedonian factions.⁴² However, Leo was not the only religious figure who attempted to appeal to Eudocia,⁴³ emphasising how even in the new political circumstances, in which Rome was more readily consulted by the Eastern emperor, the position of the pope remained as one of many authority sources and not as the only one. Leo’s politico-religious influence thus depended on the Eastern emperor’s needs and desires, and with an ecclesiastically inexperienced man as emperor, Leo utilised the situation to push the idea of universal Roman primacy.

Walter Ullmann has argued that ‘[Leo’s] contemporary emperors sensed the inherent danger’ of Leo’s claims of Roman supremacy.⁴⁴ There is no actual Leonine epistolary evidence to support this. The sections used by Ullmann, which indeed discuss the role of imperial power in Christian structures and not vice versa, are from letters addressed to Emperor Marcian after the death of Pulcheria as well as from letters to Emperor Leo (457-474).⁴⁵ Here again the context becomes crucial. Marcian was not a strong religious persona, which Leo must have known. This presented Leo with a new opportunity to exert his influence. He put forth ideas of the emperor’s focus being on mundane affairs with, of course, the implication that the spiritual domain was Leo’s, not Marcian’s.⁴⁶ It is highly unlikely that Leo would have made similar claims to Theodosius on the emperor’s role within Christendom as he now did to emperors Marcian and Leo.

Emperor Leo shared a similar background to Marcian: he was a former military man and had not been of any exceptional importance before his accession. Importantly for the bishop of Rome, Emperor Leo continued Marcian’s pro-Chalcedonian policy.⁴⁷ As Emperor Leo was not experienced in religious disputes, Pope Leo again seized the opportunity to express his views on emperor-bishop relations. Leo’s statements are bold and authoritative when defining the emperor’s role: ‘royal power was conferred on you not only for the rule of the world, but particularly for the protection of the church’⁴⁸ and ‘Realise, therefore, venerable Emperor, for how great a protection of the entire world you have been prepared by Divine Providence, and you know what assistance you owe to your Mother, the Church.’⁴⁹ However, again these statements have further context. Leo’s words were meant to urge Emperor Leo to interfere in Alexandria, which was in a chaotic and violent state in the aftermath of Chalcedon.⁵⁰ Indeed, while Leo emphasised the duty that the emperor ought to feel for the Church, he was likewise asking the emperor to act on their behalf and get involved. Leo kept his firm tone in later letters, clearly confident in his new role as a spiritual authority figure that was finally listened to in Constantinople. Pope Leo considered that it was his ‘duty to make clear what you know and to preach what you believe.’⁵¹ When taken out of context, the statements made by Leo seem bolder and more threatening than they were in the circumstances they were written in, and the consistency with which Leo was able to express his ideas does not suggest that any objection erupted in the Eastern imperial court – on the contrary, the Roman consistency helped stabilise the Church further.

Leo’s actions bring forth the question whether the views he expressed to Marcian and Leo were truly what he believed on a universal and factual level, that is to say that the imperial subjection and role of protector was applicable to all rulers at all times, or whether they were said only in reference to the specific circumstances in the Eastern power relations at the time of their composition. The answer is both. Leo’s attempts of defining the imperial role most certainly were responses to explicit situations that he exploited to his advantage, trying to exert his influence over inexperienced Eastern emperors. These circumstances brought about the vocalisation of views he had not been able to express to Theodosius or Pulcheria, and his struggles with them demonstrate that he thought his authority exceeded the power and acknowledgement that they gave him.

Vandals and Huns at the Gates of Rome

Leo is perhaps most remembered for his famous encounter with Attila the Hun in 452, when he supposedly convinced the Hunnic leader to retreat and thus Leo ‘delivered all of Italy from the peril of the enemy.’⁵² This, unsurprisingly, is hagiographical glorification, and historians now argue that Attila’s decision to retreat had to do with Emperor Marcian’s offensive against the unprotected Hunnic homelands, the spread of disease in the Hunnic army and General Aetius’s attempts to gather Hunnic troops.⁵³ Sixth century historian Jordanes also mentions superstition amongst Hunnic troops as a reason for their retreat – after all, when Rome was sacked in 410 by the Visigoths, their leader Alaric died shortly after.⁵⁴

Leo went to meet Attila on behalf of Western Emperor Valentinian III (reigned 425-455) with two senators: Trygetius, who was an ex-prefect, and Gemmadius Avienus, consul of 450.⁵⁵ Leo’s travel companions in themselves show the political nature of the journey, and perhaps because of the later emphasis on divine influence found in the hagiographical accounts – with Sts Peter and Paul appearing at Leo’s side⁵⁶ – it has been failed to understand why Leo was sent on this mission when the wrath of the Church was unlikely to intimidate Attila.⁵⁷ Religious prestige and deep spirituality were not the reasons Leo was sent. He had previous experience with diplomatic negotiations and was the most prominent figure in Rome and one of the key sources of authority in Italy in the 450s, and it was in this context that Leo was sent out. As argued by Andrew Gillett, ‘courts employed leading citizens, including clergy, as envoys, to exploit their social status.’⁵⁸ Leo’s encounter with Attila speaks of his political accomplishments and social prestige – not his spirituality. What should be taken away from the Attila encounter is that the invaders did retreat, marking a successful mission for Leo, whose image as a negotiator, politician, pope and protector were all simultaneously strengthened.

As is common with Leo’s letters, the pope himself does not mention his encounter with Attila at all. Neither does he mention his negotiations with Geiseric the Vandal or the Vandal sack of Rome in 455, an event which must have devastated Leo personally: according to the chronicler Prosper of Aquitaine, Rome was plundered for fourteen days.⁵⁹ Considering this extent of barbarian disturbances in Italy itself, it is surprising that Leo’s references to the turmoil are few and never direct. Leo mentions barbarians when discussing rape victims in North Africa,⁶⁰ a consequence of the Vandal invasions. When Emperor Marcian proposes a council in the East, Leo asks it to be postponed because at times of war not many bishops are able to attend,⁶¹ which in turn refers to the Hunnic invasion of Italy. The references to the ongoing warfare are sporadic but present throughout Leo’s pontificate: in 457 the bishop of Aquileia enquired what ought to be done to women who had remarried during their first husband’s captivity amongst barbarians and had thus been presumed dead.⁶²

When taken into consideration that Leo’s pontificate took place during a particularly eventful period in the fifth century, warfare and the barbarian armies were, perhaps, so commonplace an occurrence that they simply did not warrant special mention.

A Versatile Man

Within Italy Leo employed a secular and political role, but his letters omit much of this, emphasising his ecclesiastical side instead. The Western churches for the most part adhered to Rome, but Leo felt equally responsible for all of Christendom – the Eastern churches, however, did not acknowledge Leo’s authority over them. The ecclesiastical power play that took place during Leo’s pontificate underlines his political aura, and it was this mix of religious piety and political power that defined Leo’s relationships with secular rulers.

Leo’s power in the East was limited when he lacked efficient imperial support, but at the death of Theodosius, Leo’s luck turned. The very different outcomes of Ephesus II and Chalcedon show that Leo’s Eastern successes were dependent on who was emperor and what their religious policies were. Leo unceasingly attempted to push his authority and decisions within the Eastern imperial court, acknowledging its vitality in efficiently implementing his own ecclesiastical power. As the situation in Constantinople shifted, Leo grasped new opportunities to spread the influence of the Apostolic See. His political tact is most visible in his correspondence with emperors Marcian and Leo, showing how he intelligently and subtly used their inexperience to magnify the glory of his own see. Leo’s secular role, in the meanwhile, is amplified by his encounters with Huns and Vandals.

Leo’s authority was synonymous with the authority of Rome, which his long pontificate strengthened. He was a judge, a negotiator, a father figure and an intruder, serving several functions for his contemporaries. Current affairs rather than spiritual tradition determined the extent of Leo’s authority, threatening the Roman primacy that Leo perceived to be universal. Leo’s consistency in striving to express his own ideas, applying and modifying them in fluctuating political circumstances and frequent ecclesiastical disturbances is remarkable, having earned him the epithet ‘Great’ for his contributions to the Roman See.

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PROSPER OF AQUITAINE (2000). ‘Chronicle’, in Murray, A.C. (ed.). From Roman to Merovingian Gaul: a reader. Peterborough: Broadview Press.

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