Monday, May 12, 2025

A History of the Popes Named Leo, Part 1: Introduction, and St Leo I

The ancient Romans had a saying, “Nomen est omen – a name is a sign”, i.e., a presage about the person who bears it. Of course, this is not always or in all ways true; during my very sleepy teenage years, my mother used to joke that Gregory, which derives from the Greek word for “watchful”, was about as inappropriate a name as they come. But it is a tradition solidly grounded in the Sacred Scriptures, where there are many significant names, the greatest of all being, of course, the Holy Name of Jesus, which means “salvation”; and likewise, significant name changes, most notably that of St Peter.

Christ Consigning the Keys to St Peter, 1481/82, by Pietro Perugino, a fresco on the right wall of the Sistine Chapel.

It occurred to me, therefore, that it might be interesting to take a look at the histories of the Popes named Leo, especially since the new Pope himself has said that he chose his new name in reference to Leo XIII, who “in his historic Encyclical Rerum Novarum addressed the social question in the context of the first great industrial revolution. In our own day, the Church offers to everyone the treasury of her social teaching in response to another industrial revolution and to developments in the field of artificial intelligence that pose new challenges for the defense of human dignity, justice and labor.” (If His Holiness declares a crusade against so-called “artificial intelligence”, he shall find no more enthusiastic supporter than myself; and if he decides to expropriate the term “Butlerian jihad” for it, I shall cheer for him all the more loudly.)

First, some statistics. As of last week’s election, Leo is tied with Clement as the fourth most common papal name, behind John, Gregory and Benedict. Five of these, the first through fourth and the ninth, are Saints. Leos V-VIII reigned within a span of about 62 years in the 10th century, the first century in which there is not a single canonized Pope, but three of them for less than a year, VIII for only 82 days. The first eight lived before it was the custom for popes to take a new name upon their election, so Leo was their baptismal name.

Since that custom took root in the mid-11th century, there have been at various points some clear trends in the choices of name. From 1046 to 1145, thirteen of the eighteen Popes were “second of his name”, followed by eight “thirds” out of eleven from 1145 to 1227. From 1644-1774, there were 14 popes, all of whom were called either Innocent, Alexander, Clement, or Benedict. (Three of those names have not been used again since that period.) Seven of the twelve Piuses reigned within the 183-year span from 1775 to 1958, occupying almost 128 of those years.

Leo, however, has never been a fashionable name in that sense. The reign of St Leo IX was a watershed in the history of the papacy, and very much for the good, despite its relative brevity (five years and two months), but his name was not taken again for over four and a half centuries. XI called himself Leo in honor of X, who was related to him, and it then went into abeyance again for almost 220 years.

Pope Leo XIII (1878-1903)

Almost every series I have ever planned for NLM has been revised along the way, but for now, the plan is to cover just Leo I, a titanically important figure, in this article, followed by the next three Sainted Leos, then the four who reigned in the 10th century, Leo IX, the two Medicis (X and XI), and the two in the 19th century, XII and XIII.

St Leo I was Pope from September of 440 to November of 461, the tenth longest reign in the Church’s history. He is one of three popes traditionally known as “the Great”, along with Ss Gregory I (590-604) and Nicholas I (858-67), and with the former, one of only two recognized as Doctors of the Church, although this honor was not accorded to him until 1754. He is the first pope of whose theological writings we possess a really substantial corpus, in the form of nearly 100 sermons and over 140 letters.

He was born in Rome ca. 400, and is said to have been of a Tuscan family, but we know nothing of his early life. As a deacon of the Roman church under the sainted Popes Celestine I (422-32) and Sixtus III (432-40), he was already a very prominent figure, and received letters from St Cyril, the patriarch of Alexandria, and the great monastic writer John Cassian. It has been speculated that he was the theological mind behind the mosaic program of the basilica of St Mary Major, built in the wake of the Council of Ephesus (431) as Pope Sixtus III’s response to the Nestorian heresy. He was elected to the papacy from the diaconate, a common event in those days, while on a mission as a peace envoy in Gaul.

The central section of the mosaic arch above the altar in the basilica of St Mary Major, ca. 432 AD, with the throne of Christ, (the motif known as an etimasia), Ss Peter and Paul, and the symbolic animals which represent the four evangelists. Below them, the inscription reads “Xystus (the original form of ‘Sixtus’) the bishop for the people of God.” The Apostles are dressed as Roman senators; paired with “the people of God” in the inscription, this makes for a Christian version of the formal name of the Roman state, “the Senate and the Roman people”, a declaration that the Christian polity will outlast the collapsing Roman polity. (Image from Wikimedia Commons by RightLeft Medieval Art, CC BY-SA 4.0.)

Much of St Leo’s preaching and letter-writing was occupied with combatting the various heresies afflicting the Church in his time: not just the on-going Christological controversies, but also Pelagianism, and the Gnostic sects of the Priscillianists, who were growing in Spain, and the Manichaeans. (On discovering the existence of a group of the latter in Rome itself, he made the reception of the chalice at Mass mandatory as a way of chivying them out, since the Manichaeans abominated the consumption of wine.) Unsurprisingly, the authority of the chief of the Apostles, and of his successor, the bishop of Rome, is a frequent theme in his works, and the Roman Rite has traditionally read his sermons in the Divine Office on the various feasts of St Peter.

The Christological controversies entered a new phase during his pontificate with the invention of yet another new heresy in Constantinople. This was the creation of an abbot called Eutyches, which later came to be known as Monophysitism, the denial of the two natures, divine and human, in the one person of Christ. A second council was called together at Ephesus in 449, the infamous “latrocinium – robber-synod”, as Leo called it, in which Flavian, the orthodox patriarch of Constantinople, was subjected to such violence by the heretics that he died of his injuries not long afterwards. (He is venerated by the Church as a martyr.) Leo’s legates (one of whom, his archdeacon Hilarius, would succeed him as Pope) were forcibly prevented from reading his letter to the council, and barely escaped with their lives.

Leo himself immediately declared the council to be null and void, and wrote a letter to the emperor Theodosius II, demanding that he cease interfering with matters that fall under the authority of the Church and its bishops. Two years later, with the coming of a new emperor to the throne, and with the support of his wife, the Empress St Pulcheria, the orthodox faith was vindicated at the fourth ecumenical council, that of Chalcedon, at which Leo’s letter, known as the “Tome to Flavian”, was acclaimed with the words, “Peter has spoken through Leo.”

Contemplating the serene beauty of St Mary Major, it is difficult to imagine that when it was built, the Western Roman Empire was dangerously unstable, and close to its end. Rome had already been sacked by the Visigoths in 410, the first time it had been attacked by a foreign enemy in 800 years. In 452, just one year after the Council of Chalcedon, the Huns under Attila entered Italy, and after successfully plundering Aquileia, Milan and Pavia, turned their sights towards the capital. The military was powerless to oppose them, and it was the Pope to whom the emperor and senate turned to intervene. Leo headed north and encountered Attila near Mantua; the exact words of their meeting have not been recorded, but he was somehow able to persuade the Hun to leave Italy in exchange for a tribute. (A later tradition, repeated in the breviary, and often represented in art, but completely unhistorical, has it that the Apostles Peter and Paul appeared over Leo with swords in their hands as a way of warning Attila off.)

The Meeting of Pope St Leo I and Attila the Hun, 1514, by Raphael and students (more the latter than the former), a fresco within the rooms of Pope Julius II, now part of the Vatican Museums.

When the Vandals arrived at the gates of Rome three years later, Leo was unable to persuade them to leave off as he had Attila, but he did at least get them to refrain from massacring civilians and from burning the city. The remaining six years of his reign were much occupied with repairing the ensuing damage, especially to the churches, and to recovering the captives whom the Vandals had taken with them back to Africa. The Liber Pontificalis records that he donated new silver vessels to the churches of Rome after the sack, and renovated the “Constantinian basilica”, i.e., the cathedral of Rome, not yet called St John Lateran, as well as the basilicas of Ss Peter and Paul, establishing a monastery at the former.

The addition of the words “sanctum sacrificium, immaculatam hostiam” to the Canon is traditionally ascribed to him, but it must be said that the liturgical notices given in the Liber Pontificalis are quite unreliable. The oldest collection of Roman liturgical texts, a manuscript preserved in the capitular library of the cathedral of Verona, contains several prayers which are unmistakably based on his sermons. For this reason, its discoverer, a canon of Verona named Giuseppe Bianchini (1704-64), called it the “Leonine” sacramentary, but it is not a sacramentary, and was certainly compiled rather later than Leo’s time.

Pope St Leo I, by Francisco Herrera the Younger (1627-85)

Despite his importance, devotion to Pope Leo as a saint, both as formally expressed in the liturgy and on a popular level, has never been very prominent, especially in comparison with St Gregory. His feast day is missing from many of the earliest liturgical books of the Roman Rite, he is represented far less often in art, and, as noted above, he was not declared a Doctor of the Church until the mid-18th century. He is, however, one of the few Roman popes celebrated in the Byzantine Rite, on February 18th. In the West, the traditional day of his feast is April 11th, which is believed to be the date of one of the translations of his relics, although there is some uncertainty on this point. In the post-Conciliar Rite, his feast is kept on November 10th, the anniversary of his death. His relics are in an altar in the southwest corner of St Peter’s basilica; those of Ss Leo II, III and IV, who will be the subjects of the next article in this series, are together in the altar right next to it on the left.

The altar of Pope St Leo I in St Peter’s basilica. 

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