Michael Cerularius (c. 1000–1059)

A senatorial family of Constantinople

Michael Cerularius was born in Constantinople into a family belonging to the senatorial aristocracy of the Byzantine capital, though the exact date of his birth is not known with certainty: studies place his birth “around the year 1000”, while the most detailed biography available in French suggests a range between 1005 and 1010^[9]. This uncertainty, unremarkable for a younger son of a great family not initially destined for a leading public role, did not prevent the young Michael from entering very early upon a career in the high imperial civil service, which he pursued until 1040^[10].

The plot against Michael IV and exile on Prinkipo

In 1040, Cerularius found himself implicated in a plot to overthrow Emperor Michael IV the Paphlagonian (reigned 1034–1041), with the intention, according to Byzantine sources, of replacing him with a new emperor^[11]. The plot was discovered. Michael and his brother were exiled to the Princes’ Islands in the Sea of Marmara — to Prinkipo, to be precise^[12][13]. This punishment, relatively lenient by Byzantine standards, which often punished treason with mutilation or death, nevertheless put a definitive end to any direct political ambitions Cerularius may still have cherished within the state apparatus.

The monastery rather than power: his brother’s death

It was in this exile that Michael Cerularius’s destiny turned. His brother, struck by the same punishment, killed himself rather than survive disgrace^[14]. Michael chose another path: he took holy orders and embraced the monastic life — with, according to the interpretation most generally accepted by historians, the ambition not of fleeing the world but of recovering through the Church the road to a power now closed to him by ordinary political means^[15]. Recalled from exile under the brief reign of Michael V Kalaphates (December 1041 – April 1042), he won the favour of the new emperor Constantine IX Monomachos (reigned 1042–1055), himself a survivor of several episodes of political disgrace, who promoted him to the dignity of syncellus — a high office in the ecclesiastical administration of Constantinople, generally regarded as the step immediately preceding the patriarchate^[16].

The favour of Constantine IX Monomachos

On the death of Patriarch Alexios the Studite in 1043, Constantine IX settled his choice on Cerularius without any real synodal deliberation. The Catholic historian John Chapman, author of the Catholic Encyclopedia entry on Cerularius, summed up the scene in a formula that has remained famous: “There was no election: the emperor went straight to the mark like an arrow.”^[17]. Cerularius was enthroned on 25 March 1043^[18].

“There was no election: the emperor went straight to the mark like an arrow.” — John Chapman, Michael Caerularius, The Catholic Encyclopedia, vol. 10, 1911^[19]

This absence of normal canonical procedure is not a mere administrative detail. It immediately sheds light on a constant feature of Cerularius’s patriarchate: his legitimacy rested first on imperial favour, not on lengthy ecclesial discernment — and the man who owed his see to a stroke of court favour would, thirteen years later, turn that same logic against the emperors themselves.

A claimed title: “ecumenical patriarch”

Cerularius made conspicuous use of the title of ecumenical patriarch, borne by the bishops of Constantinople since the sixth century. The Greek term oikoumenikos denoted, in its original Byzantine sense, an honorific rank linked to the extent of the imperial oikoumene — the civilised world under Byzantine administration — and not a claim to a universal jurisdiction comparable to that which Rome claimed for the successor of Peter^[20]. The mistranslation nevertheless became, in 1054, a real point of friction: when the patriarchal chancery rendered this title into Latin as universalis, the Roman legates perceived in it a direct usurpation of pontifical primacy, while Constantinople saw in it only an ancient protocol usage^[21]. For a full analysis of the doctrinal controversy over Roman primacy, see Replies to Orthodox Objections.

A patriarchate to be standardised

The see of Constantinople which Cerularius inherited in 1043 was no longer, in the eleventh century, a mere local metropolis: since the conquests and missions of the ninth and tenth centuries, its canonical authority extended over Asia Minor, the Balkans, Bulgaria, Kievan Rus’ and Georgia^[22]. From the moment he took office, the new patriarch set about standardising religious practice across this immense territory, paying particular attention to usages deemed heterodox — notably those of the Armenian communities, accused of celebrating the Eucharist with unleavened bread and of fixing the dates of Lent differently^[23]. This policy of liturgical centralisation, pursued with an energy that even his adversaries recognised in him, directly prepared the ground for confrontation with Rome: the same liturgical grievances — azymes, Saturday fasting — would soon be turned against the Latin Church itself.

Open contempt for Rome

Historians agree in describing in Cerularius a deep-seated hostility towards the papacy and Latin usages, well before the open crisis of 1053–1054^[24]. The Byzantinist historian Martin Jugie, in the study he devoted in 1937 to the schism of Michael Cerularius in the Revue des études byzantines, describes a patriarch of energetic and haughty character, without flexibility, whose theological and historical formation remained markedly more limited than that of his distant predecessor Photius — himself the architect of a temporary schism in the ninth century, the Photian Schism^[25]. This deficit of ecclesiastical culture, combined with a temperament disinclined to nuance, fed an intransigence that neither imperial diplomacy nor Roman attempts at conciliation could bend.

The closure of the Latin churches of Constantinople (late 1052)

Towards the end of 1052, Cerularius ordered the Latin religious establishments of Constantinople — churches and monasteries run by communities of Western origin, numerous in a cosmopolitan city where Amalfitan, Venetian and Lombard merchants resided permanently — to adopt Greek liturgical usages. When they refused, he had them closed^[26]. This decision openly thwarted the policy of rapprochement then pursued by Emperor Constantine IX with the papacy, aimed at a common defensive alliance against the Norman advance in southern Italy — the same Norman threat that would lead Pope Saint Leo IX to his disastrous military campaign at Civitate in 1053^[27]. For the full context of this failed alliance and of Leo IX’s captivity, see Pope Saint Leo IX.

The episode reveals a structural tension in Cerularius’s patriarchate: the emperor sought a Western ally against a common military enemy, while the patriarch acted as the autonomous head of a Byzantine ecclesial bloc, even at the cost of openly contradicting his sovereign’s diplomacy. According to John Chapman’s account, the patriarchal chancellor is even said to have gone so far as to break into the Latin tabernacles and trample underfoot the Eucharistic species kept there, on the sole grounds that they had been consecrated with unleavened bread^[28] — a gesture of extreme symbolic violence, reported by older Catholic historiography, though not all of its details can today be verified with equal certainty.

The letter to John of Trani: the first public blow

In 1053, Cerularius had his ally Leo, Archbishop of Ohrid, draft a letter addressed to John, Bishop of Trani in Apulia (Byzantine southern Italy), but explicitly intended to circulate as far as the pope and the entire Frankish episcopate^[29][30]. The text listed the liturgical grievances Constantinople held against the Latin Church: the use of unleavened (azyme) bread for the Eucharist, Saturday fasting in Lent, and several other practices deemed contrary to the apostolic tradition received in the East^[31]. Poorly translated as it circulated towards the West, the letter was perceived in Rome as a formal provocation rather than a fraternal rebuke — a mistranslation which, from the outset, aggravated a quarrel already strained by years of Latin church closures.

Pope Leo IX replied with a doctrinally dense letter, whose Greek version circulating in Constantinople in turn departed significantly from the original Latin text: it went beyond the sole question of liturgical usages to dwell at length on the primacy of Peter and his successors^[32]. Two poorly translated texts, read by two Churches that no longer quite understood each other, thus prepared the ground for a head-on confrontation.

Niketas Stethatos and the anti-Latin pamphlet

The anti-Latin camp in Constantinople found a radical mouthpiece in the monk Niketas Stethatos (c. 1005 – c. 1090), a disciple of Saint Symeon the New Theologian and a spiritual figure venerated as a saint by the Orthodox tradition itself^[33]. In the midst of the 1053–1054 crisis, Niketas published a treatise of rare virulence against the use of unleavened bread, Saturday fasting and the marriage of Latin priests, branding their adherents with terms reported by older historiography as “dogs, evil workers, schismatics, hypocrites and liars”^[34][35].

“Dogs, evil workers, schismatics, hypocrites and liars.” — Niketas Stethatos, treatise against Latin usages, 1054, as reported by the Catholic Encyclopedia^[36]

This verbal outburst, far from being a mere isolated excess, illustrates the real temperature of the party which Cerularius encouraged and covered with his patriarchal authority. It would take direct pressure from the emperor for Niketas to be compelled, in the presence of the pontifical legates themselves, to retract his treatise publicly and throw it into the fire — a retraction which several historians judge purely formal, so closely did the man subsequently return to comparable positions^[37].

The legation of Cardinal Humbert

Pope Saint Leo IX sent to Constantinople a legation led by Cardinal Humbert of Silva Candida (also called Humbert of Moyenmoutier), accompanied by Frederick of Lorraine, Chancellor of the Holy See and future Pope Stephen IX, and by Peter, Archbishop of Amalfi^[38]. The mission reached Constantinople in early 1054, in a climate already heavily charged by the closure of the Latin churches, the letter to John of Trani and the pamphlet of Niketas Stethatos.

Cerularius, stung by what he perceived as a lack of protocol consideration — the letters borne by the legates were not, in Byzantine usage, directly addressed to him with the honours due to his rank — refused any substantive dialogue and openly challenged the very authority of the legates, arguing that Pope Leo IX, who had died on 19 April 1054, could no longer validly mandate them^[39]. This canonical objection, far from being mere bad faith, raised a genuine difficulty in law which Catholic historiography itself acknowledges: see on this point the section devoted to it in Pope Saint Leo IX. Humbert, of an unconciliatory temperament, nevertheless chose to maintain the mission and carry through to its end the mandate received during the pope’s lifetime.

16 July 1054: the bull on the altar of Hagia Sophia

On 16 July 1054, in the midst of the liturgy, Cardinal Humbert and his two companions laid on the high altar of Hagia Sophia a bull of excommunication aimed by name at Michael Cerularius, Archbishop Leo of Ohrid, the patriarchal chancellor Michael Constantine (Constantinus), and their supporters^[40][41]. Two days later, the legates left Constantinople to return to Rome^[42]. According to John Chapman’s account — a detail reported by older Catholic historiography without being equally taken up by all modern Byzantinists — Cerularius, once the legates had already departed, is said to have tried to have them brought back to be put to death, a plan which came to nothing for want of having been able to catch up with them in time^[43].

The sentence, it must be stressed precisely, was aimed neither at the Byzantine people as a whole nor even at the entire clergy of Constantinople as such: the legates took care to distinguish the emperor, the senate and the population of the capital, held to be orthodox, from the patriarch’s personal circle alone^[44]. This clarification, essential for understanding the exact scope of the rupture, is developed at greater length in The Great Eastern Schism.

Constantinople’s reply: the anathema of 20 July

Cerularius did not receive the sentence as a mere disciplinary warning aimed at his person. Four days later, on 20 July 1054, the patriarch’s Grand Tribunal in turn hurled anathema against the pontifical bull and had all copies that could be seized publicly burned, with the exception of a single one kept in the patriarchal archives^[45]. The public translation of the Latin bull into Greek provoked a riot in the capital; to calm it, the emperor had to arrest the son and son-in-law of the imperial representative in Italy, Argyros — accused of having favoured the Roman legation — and have the interpreter responsible for the translation flogged^[46].

A disciplinary quarrel between a few men could, like other fleeting tensions between Rome and Constantinople, have closed with time. But Byzantine collective memory, and then Western memory, gradually transformed this incident into the founding date of a lasting rupture between two ecclesial worlds: the Eastern Churches gradually ceased commemorating the pope in their liturgical diptychs, while the West increasingly thought of itself as the sole Roman communion, separated from an East rebellious against Petrine primacy^[47]. The analysis of the deep causes of this rupture — Filioque, Roman primacy, liturgical and disciplinary differences — is developed in full in The Great Eastern Schism and in Replies to Orthodox Objections.

It matters to measure with exactness the canonical scope of the episode in which Michael Cerularius is the central actor, without which his personal role would remain misunderstood. Catholic canon law defines schism as the refusal of submission to the Supreme Pontiff or the refusal of communion with the members of the Church subject to him^[48] — a deliberately ecclesiological definition, describing a visible breach of communion rather than a head-on denial of a precise dogma. The Catechism of the Catholic Church recalls, moreover, in the very words of the Second Vatican Council, that such ruptures occurred “sometimes through the fault of men on both sides”^[49] — a formulation which invites us to judge Cerularius’s personal responsibility without thereby making him the sole and unique architect of a historical process whose roots reach far deeper than 1053–1054.

“In fact, in this one and only Church of God from its very beginnings there arose certain rifts, which the Apostle strongly censures as damnable. But in subsequent centuries much more serious dissensions appeared, and large communities became separated from full communion with the Catholic Church — for which, often enough, men of both sides were to blame.” — Catechism of the Catholic Church, § 817, quoting the conciliar decree Unitatis Redintegratio, no. 3^[50]

What distinguishes 1054 from so many other disciplinary quarrels quickly forgotten is therefore not the intrinsic gravity of the liturgical dispute over azymes or Saturday fasting — a dispute which the Catholic Church itself today judges secondary and by no means requires to be resolved by uniformity — but the reciprocal intransigence of two strong personalities, Cerularius on one side and Humbert on the other, each acting without a sufficiently assured mandate: the first by deliberately closing every door to dialogue even before the legates arrived, the second by maintaining a solemn sentence when the pope who had mandated him was already dead. On this precise point, contemporary Catholic historiography readily acknowledges the Western share of responsibility; it locates the initiative of the rupture, however — closure of the Latin churches as early as 1052, letter to John of Trani in 1053, refusal of all negotiation in 1054 — on the patriarch’s side^[51][52].

Constantine IX Monomachos: an emperor outpaced by his patriarch

Cerularius served under Constantine IX Monomachos until the latter’s death on 11 January 1055^[53]. The policy of rapprochement with Rome pursued by the emperor, as we have seen, was already in head-on conflict with the patriarch’s action even before the rupture of 1054; after it, Constantine IX no longer had the political means publicly to disavow a patriarch who had become, in the eyes of the Byzantine people, the intractable defender of Orthodoxy against Rome.

Theodora Porphyrogenita: an enmity without sequel

The Empress Theodora Porphyrogenita, last representative of the Macedonian dynasty, reigned alone from 11 January 1055 to 31 August 1056^[54]. Cerularius apparently sought to impose upon her the choice of a husband likely to consolidate his own influence over imperial power; Theodora opposed this and thereby earned the patriarch’s lasting enmity. The historian Jean Gouillard notes that Theodora “would have deposed him from the patriarchate had long years of mortal life been granted to her”^[55] — but the empress’s death, a few months later, closed this opportunity without any sanction having been taken against him.

Maker and unmaker of emperors: Michael VI, then Isaac Komnenos

Under Michael VI Bringas (1056–1057), whom Cerularius himself crowned, the patriarch crossed openly into direct political action: he plotted with the generals Isaac Komnenos and Katakalon Kekaumenos, both publicly humiliated by the new emperor^[56]. On 8 June 1057, Isaac was proclaimed emperor by the army on his Paphlagonian estate; Michael VI, defeated in the course of the summer, abdicated at the end of August 1057 and became a monk at Hagia Sophia on Cerularius’s own advice^[57][58]. In the space of four years, the patriarch had thus helped to place the papacy in a state of rupture with his Church, and then to overthrow an emperor legitimately crowned by his own hands.

Under Isaac I Komnenos (1057–1059), Cerularius reached the summit of his political power: he obtained exclusive authority over the staff and finances of Hagia Sophia, and his nephews acceded to leading administrative posts^[59]. The historian Jean Gouillard even records that Cerularius went so far as to invoke the Donation of Constantine — that medieval apocryphal document by which Emperor Constantine is said to have ceded considerable temporal prerogatives to the pope — to claim, in his turn, privileges of a quasi-imperial nature^[60]. The historical irony is striking: the patriarch who had just broken with Rome in the name of Eastern fidelity to apostolic tradition came to rely, in order to secure his own power, on the very type of argument he had implicitly reproached the papacy for invoking in the West.

The purple boots: a patriarch dressed as an emperor

Faced with a budget deficit, Isaac Komnenos revoked the tax exemptions granted to monasteries and churches and proceeded to expropriate ecclesiastical property, relying on old legislation going back to Emperor Nikephoros II Phokas^[61]. Cerularius protested openly and threatened to overthrow the emperor as he had himself raised him to power two years earlier. He even began to wear the purple boots, a vestimentary mark hitherto reserved for the emperor alone, affirming by this symbolic gesture the equality — if not the superiority — of spiritual power over temporal power^[62].

The Byzantine chronicler Michael Psellos, a direct contemporary of the events and himself a player at the imperial court, summed up this drift in a formula that has remained famous, as reported by the Catholic Encyclopedia:

“He united in himself kingship and priesthood; he held the cross in his hand while imperial laws came forth from his mouth.” — Michael Psellos, Chronographia, as cited and translated by the Catholic Encyclopedia^[63]

An open conflict with Isaac Komnenos

The confrontation between the patriarch and the emperor he had himself raised to the throne became so insoluble that Isaac Komnenos decided to act before being himself overthrown in his turn. A climate of mutual distrust settled durably in the second half of 1058, while Cerularius, secure in his popular prestige and his grip on the finances of Hagia Sophia, no longer hid his ambitions of control over temporal power itself.

The arrest of 8 November 1058

On 8 November 1058, six days after his de facto deposition, while the patriarch was visiting a church outside the walls of Constantinople, Isaac had him arrested by the Varangian Guard — the imperial elite corps composed of Scandinavian and Rus’ mercenaries — and had him taken to Prokonnesos, an island in the Sea of Marmara^[64]. The emperor then exerted strong pressure on Cerularius to bring him to resign his patriarchal see voluntarily, without success: the old patriarch resisted to the very end any resignation^[65].

Michael Psellos’s act of accusation

To circumvent the patriarch’s resistance, Isaac Komnenos convened a synod in Thrace, deliberately held far from Constantinople where Cerularius’s popularity remained considerable, and charged his former intellectual rival Michael Psellos with drafting the formal act of accusation against him^[66][67]. This document — which historians still today describe as rich in circumstantial detail, though obviously one-sided — accused Cerularius of heresy, treason and recourse to occult or magical practices^[68]. The charge of heresy here belongs more to the political weapon than to a seriously investigated doctrinal accusation: no canonical procedure in due form would have time to establish the validity of these charges.

A death before the trial (21 January 1059)

Michael Cerularius died suddenly on 21 January 1059, in the Prokonnesos region or during his transfer to Madytos on the Hellespont, before he could appear before the tribunal convened against him^[69]. A tradition reported by the 1913 Catholic Encyclopedia mentions a shipwreck during this transfer, whose physical consequences are said to have hastened his death^[70]; this older version, however, is not taken up by all modern biographical syntheses, which more soberly record a death occurring in exile, without necessarily mentioning any shipwreck^[71]. In either case, one fact remains certain and solidly established by all the sources: Cerularius died without ever having yielded, without having resigned, and without having been formally condemned by a trial carried through to its end.

At the announcement of his death, the population of Constantinople, which venerated in him the intractable defender of Byzantine Orthodoxy against Rome, loudly manifested its anger^[72]. Isaac Komnenos, forced to retake control of the situation by force of arms alone, durably lost popularity as a result: he abdicated in his turn less than a year later, on 22 November 1059, and withdrew to the Stoudion monastery^[73]. The emperor named as Cerularius’s successor Constantine III Leichoudes, a scholar reputed for his moderation.

The paradox of Michael Psellos

The most astonishing epilogue in the story of Michael Cerularius lies perhaps in the attitude of his own accuser. Michael Psellos, charged by Isaac Komnenos with drafting the act of accusation against the fallen patriarch, pronounced his funeral eulogy a few weeks later and retrospectively described him as a misunderstood and admirable man^[74]. This reversal, far from being the mere skill of a courtier changing sides with the political wind, reflects the real place Cerularius already occupied, in his lifetime, in the Byzantine imagination: that of an intractable defender of Eastern ecclesial identity, whose hardness of character could be blamed without his cause itself being called into question.

An energetic administrator, a limited theologian

The most balanced assessment modern historiography offers of Michael Cerularius comes down to a tension. On one hand, a capable administrator of formidable energy, who succeeded in durably centralising patriarchal authority over an immense territory and in imposing himself, in the space of some fifteen years, as the true arbiter of power in Constantinople^[75]. On the other, a man whose theological and historical formation remained, in the very judgment of the Byzantinists, markedly inferior to that of his greatest predecessors, and whose intolerance of liturgical diversity — yet a traditional characteristic of the undivided Church of the first ten centuries — directly fed the escalation of 1053–1054^[76].

Unlike Photius, whose ninth-century schism was followed by a formal reconciliation and whose memory is venerated as that of a saint and Father of the Church by Orthodox tradition, Michael Cerularius was never the object of a canonisation nor received a liturgical feast of his own in the Byzantine calendar — a contrast not mentioned by the Orthodox hagiographical reference sources consulted for this article^[77]. His immediate successors nevertheless instituted annual commemorations in his honour, a sign of lasting popular esteem which does not, however, amount to official recognition of sanctity^[78].

1965: Paul VI and Athenagoras lift the sentence

Nine centuries after the events, Pope Saint Paul VI and Ecumenical Patriarch Athenagoras I chose, on 7 December 1965, at the close of the Second Vatican Council, to make a gesture directly addressed to the memory of Michael Cerularius. Their joint declaration explicitly recalls “the memory of the decisions, acts and painful incidents which in 1054 led to the sentence of excommunication pronounced against Patriarch Michael Cerularius and two other persons by the legates of the Roman See, led by Cardinal Humbert”^[79].

“[Paul VI and Athenagoras I declare that they] regret […] and remove from memory and from the midst of the Church the sentences of excommunication which followed them […].” — Paul VI and Athenagoras I, Joint Declaration, 7 December 1965, § 4^[80]

The text takes care to specify that the censures of 1054 “concerned the persons aimed at and not the Churches, and were not intended to break ecclesiastical communion”^[81] — confirming a posteriori, by the most authoritative voice there is, the analysis already developed above on the strictly personal scope of the 1054 sentence. The name of Michael Cerularius, erased from the memory of the excommunication that had weighed upon him for nine centuries, nevertheless remains inseparable from the history of a rupture whose ecclesial consequences are still not overcome. For details of later attempts at union — Lyons II, Florence — and of the present state of relations between Catholics and Orthodox, see Replies to Orthodox Objections and The Great Eastern Schism.

The following table situates Cerularius’s patriarchate against the four successive imperial reigns it spanned, between his appointment in 1043 and his death in exile in 1059.

• The Great Eastern Schism — the full analysis of the causes, doctrinal stakes and lasting consequences of the 1054 rupture.
• Pope Saint Leo IX — the pope whose legation, sent before his death, led to the sentence of 16 July 1054.
• Replies to Orthodox Objections — the complete doctrinal dossier: Filioque, pontifical primacy, azymes, and the lifting of the 1965 anathemas.
• The Photian Schism — the first great crisis between Constantinople and Rome, two centuries before Michael Cerularius.
• Saint Paul VI — the pope who lifted, in 1965, the sentence pronounced against Cerularius nine centuries earlier.
• The Second Vatican Council — the council at the close of which the 1965 joint declaration was solemnly read.

Visual sources: mosaic of Constantine IX and Zoe^[99], interior of Hagia Sophia^[100], histamenon of Isaac I Komnenos^[101] and miniature of Michael Psellos^[102].