The Great Schism

Summary

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History Daily: "The Great Schism" (July 16, 2026)

Episode Overview

In this episode of History Daily, host Lindsay Graham transports listeners to July 16, 1054, the day that marked the formal beginning of the Great Schism—the permanent division between the Western (Roman Catholic) and Eastern (Orthodox) branches of Christianity. Graham reconstructs the charged events in Constantinople’s Hagia Sophia as Cardinal Humbert, sent from Rome, delivers a papal bull of excommunication to Patriarch Michael Ceruleus. The episode dives into the political, religious, and cultural tensions that culminated in this rupture, highlighting the long history of disputes between East and West and setting the stage for centuries of Christian division.

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Key Discussion Points & Insights

The Immediate Moment: Excommunication in Hagia Sophia

• Dramatic Scene-Setting (00:39)
  • July 16, 1054, Hagia Sophia, Constantinople: Cardinal Humbert marches through the cathedral, disrupting prayer to deliver a papal bull of excommunication against Patriarch Michael Ceruleus.
  • This act symbolizes the crescendo of long-standing tensions between Rome and Constantinople.
  • Quote (Lindsay Graham, 01:38):

    "Dozens of eyes fix on the seal at the top of the parchment... This is the papal seal and the document is a deed of excommunication. It means banishment from the Church and it's addressed to Michael Ceruleus."

Historical Foundations of the Rift

Charlemagne’s Coronation and the Emerging Divide (04:40)

• Charlemagne Crowned "Emperor of the Romans"
  • On Christmas Day, 800 CE, Pope Leo III crowns Charlemagne, creating overlapping imperial claims with the Byzantine Empire.
  • This coronation ignites political and ecclesiastical rivalry.
• Custom and Doctrinal Disputes
  • Christianity, though theoretically unified under five patriarchs (Rome, Constantinople, Jerusalem, Antioch, Alexandria), faces growing internal disputes:
    • Language (Latin vs. Greek)
    • Ritual (leavened vs. unleavened bread)
    • Authority disputes among patriarchs
• The "Filioque" Controversy
  • Western changes to the Nicene Creed—adding "and the Son" (filioque) as a source of the Holy Spirit—met fierce Eastern resistance.
  • Quote (LG, 07:15):

    "Some argue that the addition is heretical. Others don't go so far. But they’ll all argue that changing the Nicene Creed without the agreement of Church leaders is completely unacceptable."

Rise of the Patriarchs and Papal Authority

• Decline of Shared Power
  • As the influence of the five patriarchs system declines, the Pope seeks ultimate authority in the West, while Constantinople becomes the clear Eastern leader.
  • Michael Ceruleus embodies Eastern resistance to perceived Roman overreach.

The 1054 Showdown in Constantinople

Cardinal Humbert’s Mission (11:58)

• Latin vs. Greek Practices

  • Humbert travels to Constantinople after Patriarch Michael Ceruleus tramples upon Latin customs and shutters Western churches.
  • Quote (LG, 13:20):

    "To Caeruleus, [Western customs] represented more than harmless variation within a shared tradition. They were a sign of growing and unwanted papal influence in his own city."

• Diplomacy Breakdown

  • Efforts to meet fail—Ceruleus delays or avoids engagement.
  • Humbert learns that his mandate may have lapsed with the death of Pope Leo IX yet chooses to escalate rather than withdraw.

• Delivery of the Papal Bull (15:53)

  • Humbert formally excommunicates Ceruleus in the Hagia Sophia, an act of theatrical and spiritual provocation.
  • Quote (LG, 15:53):

    "As Humbert walks out of the building past a shocked congregation, he stops briefly in the church doorway. There he dramatically shakes the dust from his robes as if cleansing himself of the taint of Eastern Christianity."

• Ceruleus Responds (18:18)

  • Ceruleus convenes a synod, and the Eastern bishops retaliate by excommunicating Humbert and his delegation—the divide is now formalized by both sides.
  • Quote (LG, 18:53):

    "They declare that Humbert and the rest of his delegation are henceforth Christ cut off from communion with the Church in Constantinople. Rome has cast out the patriarch. But now the Patriarch has cast out Rome."

Legacy and Consequences

• Initial Hope for Reconciliation
  • Many in both camps expect the break to be temporary. Unity had previously survived flare-ups.
• Enduring Schism
  • The schism becomes permanent, inflamed further by later events like the 1204 sack of Constantinople during the Fourth Crusade.
  • The two branches—Roman Catholic and Eastern Orthodox—remain separate for centuries.
  • Quote (LG, 20:35):

    "The result is a permanent division between the churches of east and west, creating separate Roman Catholic and Eastern Orthodox churches that exist to this day."

  • The episode closes by reflecting on the deep, enduring consequences of the Great Schism, with reverberations through ecclesiastical, political, and cultural history.

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Notable Quotes & Memorable Moments

• Cardinal Humbert’s Defiance (15:53)

  "He stops briefly in the church doorway. There he dramatically shakes the dust from his robes as if cleansing himself of the taint of Eastern Christianity."

• Eastern Church’s Response (18:53)

  "They declare that Humbert and the rest of his delegation are henceforth Christ cut off from communion with the Church in Constantinople."

• On the Schism’s Permanency (20:35)

  "After centuries of growing tension, this is a point of no return. Relations between the Latin and Greek churches continue to deteriorate..."

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Timeline of Critical Moments

• 00:39 — Humbert delivers the excommunication in Hagia Sophia
• 04:40–09:49 — Origins of division: Charlemagne’s coronation, split in customs and doctrine
• 11:58 — Cardinal Humbert’s mission to Constantinople
• 15:53 — Humbert publicly excommunicates Ceruleus
• 18:18 — Ceruleus calls the synod; mutual excommunications are formalized
• 20:35 — Long-term consequences: the permanent rift between East and West

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Conclusion

Lindsay Graham’s retelling of the Great Schism on History Daily presents a vivid dramatization of the events and deeper historical forces leading to the most profound split in Christian history. The narrative brings listeners inside the pivotal moments, from power politics to passionate debates over doctrine, illustrating how centuries of evolving traditions and rivalries exploded into open division that shaped the Christian faith—and Europe—ever after.

Transcript

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[Lindsey Graham]

It's the afternoon of July 16, 1054, at the Hagia Sophia in Constantinople. The papal ambassador, Cardinal Humbert strides through the great bronze doors of the cathedral. Marble columns rise on either side of him, supporting a vast domed ceiling overhead with golden mosaics cover the walls and vaults. A sea of worshippers turns around to look at him. Humbert has arrived at the beginning of the afternoon service and chanting prayers fill every corner of the ancient church. But Humbert is not here to pray. He has been sent to Constantinople from Rome to negotiate with Patriarch Michael Ceruleus, the most powerful church leader in the Eastern Christian world. But Caerulius has ignored and insulted him. And now Humbert has run out of patience. He marches down the vast marble nave, the sound of his steps cutting through the chanting. Priests and worshipers pause mid prayer as he passes, but no one moves to stop him. When he comes to the altar, Humbert reaches into his robes and produces a parchment. He drops it onto the altar and lets it unfurl. Dozens of eyes fix on the seal at the top of the parchment and a ripple moves through the congregation as people recognize it. This is the papal seal and the document is a deed of excommunication. It means banishment from the Church and it's addressed to Michael Ceruleus. Tensions have been building between the Christians of East and west for centuries. In the past, Rome and Constantinople have been able to patch up their differences and remain united as one church. But now relations between the two have reached a breaking point. And one of the most consequential religious rifts in history will be triggered when Cardinal Humbert excommunicates the Patriarch of Constantinople on July 16, 1054.

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[Lindsey Graham]

from Noiser and airship. I'm Lindsey Graham, and this is History. Daily. History is made every day on this podcast. Every day, we tell the true stories of the people and events that shaped our world. Today is July 16th, 1054. The great schism. It's Christmas Day 800 CE at St. Peter's Basilica in Rome, 254 years before Cardinal Humbert excommunicates the patriarch of Constantinople, Charlemagne, the King of the Franks, kneels at the altar as Pope Leo III leads the congregation in prayer. The great church is lit by hundreds of candles, and a heady mix of smoke and incense hangs in the air. At the age of 52, Charlemagne is the most powerful man in Europe. He has crushed rivals in battle and absorbed fractured kingdoms through diplomacy. He now rules more territory than any other king in generations. And yet he considers today to be his greatest achievement. A large congregation of nobles from across Charlemagne's empire has gathered for this ceremony. They watch in reverential silence as the prayers come to an end and Pope Leo steps forward carrying a large golden crown. Charlemagne stares forward slowly. Leo lowers the crown onto his head and proclaims Charlemagne Emperor of the Romans. It's a title that no one in Western Europe has claimed for centuries. There's just one problem. The Roman Empire still exists, and it does not need a new emperor. Although the Western Roman Empire collapsed in the 5th century, in the east, the empire survived. Ruled from the city of Constantinople, the Eastern Empire is universally recognized as the last remnant of the once mighty Roman state. But Charlemagne's coronation threatens that still, his rise doesn't just present a political challenge to the Eastern Empire. It also strikes a blow against the fragile unity of Christianity itself. On paper, Christians in both east and west belong to one unified Church, with power shared by patriarchs from the five great cities of Christendom, Rome, Constantinople, Jerusalem, Antioch and Alexandria. In practice, though, many different customs and traditions coexist within Christianity, and there are frequent disputes between the five patriarchs. For centuries, these disagreements over power and theology have been manageable. But Charlemagne's emergence as Emperor of the Romans opens up new divisions. One dispute centers on a statement of belief that dates back to the 4th century. The Nicene Creed originally stated that the Holy Spirit comes directly from God the Father. But gradually, over the centuries, churches in Western Europe began adding and the Son to that formula. Now, Charlemagne pushes for the phrase to be universally adopted. Most churches within his empire accept the change, but in the east, they fight back. Some argue that the addition is heretical. Others don't go so far. But they'll all argue that changing the Nicene Creed without the agreement of Church leaders is completely unacceptable, and that not even a man as powerful as Charlemagne has the right to alter a statement of belief shared by all Christians. So Charlemagne does not get his way. His efforts help standardize Christian worship in his own territories. But the original Nicene Creed continues to be used elsewhere, unchanged. Charlemagne dies in 814 CE, and the vast empire he built breaks apart soon after. But the dispute over the wording of the Nicene Creed does not end there. For more than 200 years after Charlemagne's death, the argument drags on. The reference to the Son as well as the Father continues to feature in the liturgy of Western churches, But Eastern churches continue to reject the addition. Over the years, positions harden, divisions widen, and the argument over the Nicene Creed becomes just part of a wider power struggle in the Christian world. And as the old system of the five patriarchs begins to crumble, the Pope in Rome tries to claim ultimate authority in the Church. And Constantinople emerges as the main power opposing him in the east. Eventually, in the 11th century, a new religious leader will rise in the city, a man who will see Rome not as a potential partner in faith, but as a threat. The new patriarch of Constantinople is Michael Ceruleus, and he is ambitious, stubborn, and fiercely protective of his authority. He will have little patience for Western influence in the east and will challenge Rome directly. When he does, the fragile balance between east and west will finally shatter.

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[Lindsey Graham]

It's April 1054 at a market square in Constantinople, over 250 years after Charlemagne's coronation, Cardinal Humbert climbs down wearily from his carriage and stretches his legs. Weeks after setting off from Rome, the exhausted Humbert has finally reached his destination. He wipes the dust from his face and takes his first look around the city he's heard so much about. Unlike many of the travelers he saw on the road to Constantinople, Humbert is not a pilgrim. He's here to deal with a crisis on behalf of Pope Leo ix. In recent months, the Patriarch of Constantinople, Michael Caerulius, has become increasingly hostile toward the Western churches operating in his city. Western priests follow different rituals and customs from their Eastern counterparts. These extend even to the most basic details of Christian worship. The Western church services are conducted in Latin, while Eastern churches use Greek. Western communion bread is made without yeast and entirely flat, while the Eastern is risen and leavened. But it wasn't these differing traditions that seemed to provoke the patriarch. To Caeruleus, they represented more than harmless variation within a shared tradition. They were a sign of growing and unwanted papal influence in his own city. So in 1052, he ordered the Latin churches in Constantinople to follow Greek rites. When they refused, he shut them down. Adding insult to injury, Caerulus did not just have the doors to the Latin churches barred, but the flat communion bread they used trampled in the streets. When word of this outrage reached Rome, Pope Leo IX was furious. Such an insult cannot be ignored. So Leo sent his most trusted advisor to Constantinople for talks with Caerulius. Officially, Humbert and his legation arrive as diplomats tasked with repairing relations between Rome and Constantinople. But although he's a brilliant scholar, Humbert is not known for his patience or his tact. He hasn't been sent here to build bridges, he's been sent here to fight. But from the moment he enters Constantinople, his mission begins to unravel. Humbert wants to meet with the Patriarch directly, but that proves impossible. Requests for an audience aren't officially rejected, but the talks are repeatedly delayed. Weeks go by, excuses wear thin, and Humbert's frustration with this open show of defiance only grows. Humbert may be angry and think he speaks with the power of Rome behind him, but as far as Caerulius is concerned, Humbert is just an advisor who has no right to lecture him. And besides, Caerulius rejects the very idea that as Patriarch of Constantinople, he should defer to the Pope in any way. Neither man is interested in compromise, and neither is willing to back down. But then, suddenly, the situation shifts again. A courier arrives from Rome with an urgent message for Cardinal Humbert. Pope Leo IX is dead. For Humbert, the news is potentially disastrous. His authority in Constantinople was personal, granted directly by the Pope, who appointed him. Under normal procedure, that authority would end the moment the Pope dies. And Humbert will be expected to return to Rome and await further instructions from a successor. But leaving Constantinople now would hand victory to Caerulius. Who will think he has the authority to defy Rome again? So Humbert decides that he will stay and fight. Over the following weeks, Humbert assembles his case against the patriarch. Clerics draft a language that accuses Servulius of defying Rome and leading Christians away from proper teaching. And slowly a papal bull of excommunication takes shape. This is the most severe punishment in Christianity. The document formally casts Michael Ceruleus out of communion with the Roman church. And on July 16, 1054, Humbert enters the Hagia Sophia cathedral and places the bowl of excommunication on the altar. As Humbert walks out of the building past a shocked congregation, he stops briefly in the church doorway. There he dramatically shakes the dust from his robes as if cleansing himself of the taint of Eastern Christianity. Then he sweeps out of the cathedral. A deacon runs after him into the street and waiving the papal edict and begging him to take it back. But Humbert refuses. For him, the matter is settled. But for Patriarch Michael Caerulius, it's only just beginning. He is not prepared to let Rome's decree stand unanswered. But when he responds, the consequences will extend far beyond Constantinople.

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[Lindsey Graham]

It's July 24, 1054, in Constantinople, only a week after Michael Ceruleus was excommunicated. Ceruleus moves quickly through the corridors of the patriarchal palace. Messengers fall into step beside him, speaking in urgent bursts. Copies of the papal edict are already circulating among clergy in Constantinople, its contents read and repeated in guarded voices. In response, Caerulius has summoned the senior bishops of the Eastern Church to an emergency council known as a synod. And inside a cavernous hall, bishops take their places in uneasy silence. Ceruleus is outraged by Cardinal Humbert's edict, but he listens calmly as the bishops debate what to do about it. Some demand immediate retaliation. Others urge restraint, worried that the ancient unity of the Church will be put at risk by any hasty response. But ultimately, accepting the decree would mean accepting Rome's authority over the Patriarch of Constantinople. And Caerulius will not have that. Scribes are called forward, and Caerulius and his advisors begin drafting a declaration of their own. In this document, they argue that the east is the one true protector of the Christian faith. And they declare that Humbert and the rest of his delegation are henceforth Christ cut off from communion with the Church in Constantinople. When the text is complete, it is carried beyond the palace walls to be read publicly and distributed among the Western clergy still present in the city. Rome has cast out the patriarch. But now the Patriarch has cast out Rome. It's a dramatic development, but at first, few in Rome or Constantinople believe it will lead to a permanent rift. Disputes between east and west west have erupted before, and new leaders, new negotiations and new political circumstances have always restored relations. Eventually, even within the Eastern Synod itself, some bishops expect to return to the status quo once tempers cool. But this time is different. After centuries of growing tension, this is a point of no return. Relations between the Latin and Greek churches continue to deteriorate, reaching a new depth in 1204, when a crusader army from Western Europe sacks Constantinople. The result is a permanent division between the churches of east and west, creating separate Roman Catholic and Eastern Orthodox churches that exist to this day. The Great Schism was the deepest rift in Christian history, with consequences that echoed through the centuries. And it was ignited by a disputed papal bull of Excommunication, delivered on July 16, 1054. Next on History Daily, July 17, 1674. Two skeletons are discovered in London, leading to speculation that they are the long lost princes in the tower. From Nouser and airship. This is History Daily, hosted, edited and Executive produced by me, Lindsey Graham Audio editing by Mohammed Shazi Sound design by Molly Bond Music by Thrum. This episode is written and researched by Olivia Jordan Edited by William Simpson Managing Producer, Emily Burke Executive producers are William Simpson for Airship and Pascal Hughes for Nouser.

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