Historically, the first pope to be called "the Great" was Leo I (pope 440–461), whose leadership during the collapse of the Western Roman Empire established a standard for using the Latin title Magnus to denote doctrinal strength, moral authority, and expansive pastoral care. Before Leo, early bishops were sometimes praised in regional letters, but the formal and enduring use of "the Great" begins with his recognition in late antiquity, consolidating a tradition that would later be applied to Gregory I, Nicholas I, and others. This profile explains the origins of the title, the evidence from early medieval sources, and why Leo I is widely treated in modern scholarship as the first unequivocal "great" pope.
Defining papal greatness in late antiquity
The early use of "the Great" for bishops
In the first centuries of Christianity, honorific epithets for bishops were common but varied widely by region and writer. Terms like magnus (great), sanctus (holy), and pater (father) appeared in sermons, letters, and liturgical commemorations. What distinguished the title "the Great" was not mere size or influence, but a combination of doctrinal clarity, moral stature, and effective governance that preserved unity across a fragile and fragmented empire. Leo I crystallized these expectations, setting a durable template for how subsequent popes would be judged and commemorated.
Leo I and the consolidation of papal authority
Leo I is credited with transforming the bishop of Rome into a more visible and authoritative teacher of the faith, intervening in imperial affairs, and negotiating with barbarian leaders to protect the city. His Tome to Flavian, presented at the Council of Chalcedon (451), articulated a two-nature Christology that was widely influential and reinforced the idea that the pope could speak with decisive clarity on doctrine. Contemporary historians such as Prosper of Aquitaine describe him as summus apostolus (supreme apostle) and magnus, providing early textual evidence for the use of "great."
Evidence from early sources
Patristic writings and councils
Several fifth- and sixth-century sources refer to Leo I with language that later tradition condensed into "the Great." In post-Chalcedonian readings of his letters and sermons, he is portrayed as a second Peter whose interventions corrected wayward bishops and preserved orthodoxy. While later medieval authors embellished these accounts, the core claim that Leo was regarded as spiritually and juridically exceptional is well attested in contemporary or near-contemporary texts.
From Leo to Gregory and beyond
After Leo, the title appeared sporadically. Gregory I (590–604) came to be called "the Great" in the high Middle Ages, but early medieval writers used phrases such as Gregorius magnus more selectively. Other popes such as Nicholas I (858–867) also earned the epithet in particular contexts, but Leo I remains the earliest figure consistently identified in modern reference works as the first pope explicitly honored with the sustained designation "the Great." The following table summarizes key attributes and attestations relevant to this claim.
| Attribute | Verified Detail | Source Type |
|---|---|---|
| Pope | Leo I (440–461) | Consensus across modern reference works |
| Earliest consistent use of "the Great" | Late fifth-century sources, post-Chalcedonian references | Patristic texts and medieval chronicles |
| Latin designation | Leo speaks of himself as Magnus in influential contexts | Letter corpus and sermon tradition |
| Council involvement | Tome to Flavian at the Council of Chalcedon (451) | Fifth-century conciliar records and later histories |
| Title consolidation | By the ninth century, writers commonly label Leo I as Leo Magnus or Leo the Great | Medieval annals and hagiographies |
How the title functioned in medieval perception
Moral and political authority
Medieval audiences understood "the Great" as shorthand for a pope who combined doctrinal fidelity with tangible impact on public order. Leo I's role in persuading Attila to abandon the sack of Italy, his governance of Roman estates, and his liturgical reforms made him a symbol of a church that could stabilize a collapsing world. Calling a pope "the Great" thus signaled not only personal sanctity but also effective leadership in crises.
Narrative and liturgical reinforcement
Hagiographic texts, liturgical calendars, and sermons amplified Leo's reputation, embedding the epithet in liturgical hymns and local devotions. By the Carolingian period, the formula Leo Magnus or Leo the Great was widespread in chant and chronicles, cementing the association between the name Leo and greatness in the collective memory of Western Christendom.
Later popes and the use of the epithet
Gregory I and the spread of the model
Gregory I (590–604) is the most frequent recipient of the title after Leo I. His prolific writings, missionary policies, and administrative reforms led medieval authors to call him Gregorius magnus. Yet Gregory himself rarely uses the language of greatness in his own letters, suggesting that the label was applied retrospectively as communities sought to signal exemplary papal leadership.
Other candidates and criteria
Subsequent popes occasionally earned the epithet in specific contexts—for instance, Nicholas I for his moral rigor and defense of canon law—but none displaced Leo I as the earliest and most consistently recognized instance of the formal designation. Modern criteria for calling a pope "the Great" typically emphasize doctrinal contributions, lasting influence on church structure, and moral authority recognized across regions and generations.
Modern scholarly consensus
Contemporary historians of late antiquity and the early medieval church generally agree that Leo I was the first pope consistently described as great in surviving sources. While debates continue about the precise character of his influence and the reliability of later hagiography, the core judgment that Leo I pioneered a new model of papal greatness is widely accepted. This consensus is reflected in current encyclopedias, reference works, and teaching materials used in universities around the world.
Why the distinction matters today
Identifying the first pope called the Great is more than a matter of antiquarian curiosity; it clarifies how Christian communities have long evaluated leadership in terms of doctrine, governance, and crisis response. Leo I's example laid a benchmark against which later popes were measured and helps modern readers understand the deep roots of the language used to describe papal authority. For scholars, catechists, and engaged believers, knowing the origins of this title enriches both historical understanding and contemporary reflection on religious leadership.
For these reasons, Leo I stands as the definitive answer to which pope was the first called the Great, offering a durable point of reference for anyone studying the development of papal honorifics and their significance in Christian history.