From New World Encyclopedia
Leo III Mosaic.jpg
Birth name Unknown
Papacy began December 27, 795
Papacy ended June 12, 816
Predecessor Adrian I
Successor Stephen IV
Born Date of birth unknown
Rome, Italy
Died June 12 816
Place of death unknown
Other popes named Leo

Pope Leo III (died June 12, 816) was Pope from 795 to 816. Pope Leo III is best known for crowning Charlemagne as the first Holy Roman Emperor and for promoting the vision of the Christian world as a single, orderly, peaceful society under the ultimate authority of the Bishop of Rome as Christ's deputy on earth. This understanding of the papacy claimed temporal as well as spiritual power, symbolically represented by the imperial dress that the popes wore, the purple mantel and scarlet tunic. Leo pioneered what became the king-making role of Popes, although the actual relationship between papacy and the temporal powers was never as simple as the doctrine of the monarchical supremacy of the papacy implied. Nonetheless, as a result of his legacy, Europe remained a more unified, peaceful society with a greater sense of co-responsibility and of a common, Christian identity that transcended national borders. This had implications, for example, in the legal sphere, since ecclesiastical law was the same across Europe, even if civil law differed. The Church's near monopoly on education, too, meant that it trained the scholars and the lawyers, who tended to share the single-society view of the Christian world.


Leo was the son of Atyuppius and Elizabeth. Unlike many of the Cardinals and those who entered the papal household, he was not a member of the nobility. Little is known about his early life. He rose through the ranks of the papal clerical hierarchy to become a Cardinal Priest, and Treasurer. His election as Pope, however, on the day that his predecessor, Adrian I died, was unanimous. However, he appears to have aroused the hostility of Rome's nobility, who saw the papal post as reserved for noble candidates. Possible, this hostility was aroused when, straight after his consecration, Leo sent the keys of Rome to Charlemagne, indicating that he recognized the Frankish king, with whom Adrian I had enjoyed a close relationship, as Rome's protector. The Roman aristocrats would have resented placing Rome under the protection of a non-Roman. In April 799, Leo was attacked by a gang whose members included a nephew of his predecessor, who attempted to gouge out his eyes and cut off his tongue. He was accused of adultery and perjury. He was then formally deposed and sent to a monastery, but escaped and made his way to Charlemagne, who escorted him back to Rome under royal protection.

Crowning of Charlemagne

On Christmas Day, Leo placed the imperial crown on Charlemagne's head, resurrecting the office of Emperor of the Roman Empire, which became known as the Holy Roman Empire.

Charlemagne went to Rome in November 800, and on December 1, held a council there with representatives of both sides. Leo, on December 23, took an oath of purgation concerning the charges brought against him, and his opponents were exiled. Two days later Leo crowned Charlemagne after the latter prayed at St. Peter's tomb.

The groundwork for the arrangement by which the Pope crowned the Emperor, and claimed by so doing ultimate temporal as well as spiritual authority as Christ's deputy, or substitute (vicar) on earth had already been laid by Adrian I and by the document (later proved a forgery) known as the Donation of Constantine. In this document, which purported to be the last will and testament of Constantine I, the Roman Emperor appointed the Bishop of Rome as his successor. The Declaration also entitled the Pope to wear the symbols of imperial office:

we by this present do give our imperial Lateran palace, then the diadem, that is, the crown of our head, and at the same time the tiara and also the shoulder-band,-that is, the strap that usually surrounds our imperial neck; and also the purple mantle and scarlet tunic, and all the imperial raiment; and also the same rank as those presiding over the imperial cavalry, conferring also even the imperial scepters, and at the same time all the standards, and banners, and the different ornaments, and all the pomp of our imperial eminence, and the glory of our power.

[1] Although it purports to have been written by Constantine, and refers to Pope Sylvester, it may have been Adrian I who referenced the text for the first time.

Leo III's namesake, Leo I had also laid groundwork for this understanding of papal authority with his doctrine of the ecclesiastical supremacy while at the same time he effectively positioned the papacy to emerge as the only viable power in what had been the Western Roman Empire. Once the empire had collapsed, and former Roman provinces became independent, law and order was more or less a casualty of the general break-up of the former imperial system. It was by asserting his moral authority, and the doctrine of the unity of the church and of Christian society as a single entity, that Pope Leo I and his successors rescued some semblance of European unity. Johnson writes:

In the West, the Church had imposed Christian characteristics on the law, it had achieved a dominant role in the agrarian economy, and it has established a monopoly of education and culture. Now it had the chance to integrate the basic system of government with Christian teaching and practice by making the ruler a functionary of Christian theology.[2]

The empire may have crumbled but if the Pope's blessing was necessary for any king to be recognized as legitimate, even though power was vested in many and not in a single temporal ruler, there was one ultimate authority, the Pope. This was also supported by much Roman Law, which was also generally recognized. There is little doubt that Charlemagne saw himself as superior to the Pope, since without his protection, the Pope would not survive. On the other hand, since there was no automatic right of succession in Frankish law, the church's blessing was understood as a necessary, sacramental seal of succession. If the Pope claimed to be the "residual legatee of the" Roman "empire in the west," as expressed in the Donation of Constantine, it seems that as far as the Emperor was concerned, he was "head of the church as well as head of the State."[3] Charlemagne, however, is said to have truly loved him. Historian Paul A. Johnson suggests that at this time, it was believed that the end of one reign and the start of the next required sacramental intervention to "break the magic of the old line" and transfer this "to the new."[4] As head of the church, the Pope was the senior sacramentalist, so was in prime position to confirm the king's authority. If nominally this made the Pope superior, in reality Charlemagne knew that since the Pope needed his protection, he was "therefore inferior," whatever the Church itself taught.[5]

Political interventions

Leo helped restore King Eardwulf of Northumbria, and settled various matters of dispute between the Archbishops of York and Canterbury. He also reversed the decision of his predecessor in regards to the granting of the pallium (the symbol of the rank of archbishop) to the bishop of Lichfield, Higbert. He believed that the English episcopate had been misrepresented before Hadrian and that, therefore, his act was invalid. In 803, Lichfield was a regular diocese again.

Leo forbade the addition of "filioque" (the spirit as proceeding from the Father and from the Son, always opposed by the Eastern Church) to Nicene Creed which was added by Franks in Aachen in 809. He also ordered that the Nicene creed be engraved on silver tablets so that his conclusion might not be overturned in the future. He wrote "HAEC LEO POSUI AMORE ET CAUTELA ORTHODOXAE FIDEI" (I, Leo, put here for love and protection of orthodox faith) VITA LEONIS, LIBER PONTIFICALIS.

Following Charlemagne's death (814), the nobles of Rome again attempted to rebel against Leo. He had some of the conspirators imprisoned and executed but did not himself survive the Emperor for very long, dying in 816. He was succeeded by Stephen IV.

Buried in St. Peter's, his relics lie close to those of Leo I, Leo II, and Leo IV. During the reign of Leo X, he was immortalized by Raphael bearing the images of the Medici pope.


Leo was also an effective administrator of the papal territories and contributed to the beautification of Rome. Leo's main legacy was the creation of the Holy Roman Empire and his vision of a single, peaceful, orderly society ruled by a single authority, the papacy, whose spiritual assistants were the clergy and whose temporal assistants were the princes and kings. In reality, the relationship between Popes and the Emperors was always complex, with the latter never really conceding the doctrine of papal supremacy in the temporal realm, yet depending on the Popes for their own legitimacy. Force of arms alone was not enough, as there were always other kings vying for the imperial title. When the Avignon exile of the Papacy began in 1305, Philip IV The Fair of France was strong enough to control the papacy, although he was not the Emperor. Philip regarded his own rule as divinely ordained, and the Pope as his servant, not vice-versa. The reality of the medieval papacy was a struggle for authority, with the Popes viewing kings as their servants and kings seeing the popes and bishops as servants of the state. In fact, it was during Philip's dispute with Pope Boniface VIII that the latter expressed the classical dogma of papal supremacy in his bull, Unam Sanctam, in which he states:

Both, therefore, are in the power of the Church, that is to say, the spiritual and the material sword, but the former is to be administered _for_ the Church but the latter by the Church; the former in the hands of the priest; the latter by the hands of kings and soldiers, but at the will and sufferance of the priest.

However, one sword ought to be subordinated to the other and temporal authority, subjected to spiritual power.[6]

This also created the investiture controversy between popes and lay rulers about who had the authority to appoint bishops. On the one hand, the papacy never acquired its own military capability to any real extent. On the other hand, it was a wealthy institution and some bishops combined spiritual with temporal jurisdiction, which made these sees very attractive to men who had little interest in the priestly life. Sometimes, bishops appointed by kings (or who paid for their appointments) were not even ordained. Leo was declared a Saint in 1673. His feast day is June 12.


  1. Hanover Historical Texts Project, The Donation of Constantine. Retrieved October 10, 2007.
  2. Ibid., 170
  3. Paul A. Johnson, History of Christianity (New York: Atheneum, 1987). ISBN 0689705913
  4. Ibid., 172
  5. Ibid., 173.
  6. Boniface VIII, [Unam Sanctam, 1302. Retrieved October 10, 2007.

ISBN links support NWE through referral fees

  • Hibbert, Christopher. The Popes. Chicago: Stonehenge, 1982. ISBN 9780867060249
  • McBrien, Richard P. Lives of the Popes The Pontiffs from St. Peter to John Paul II. San Francisco: HarperSanFrancisco, 1997. ISBN 9780060653033
  • Sypeck, Jeff. Becoming Charlemagne Europe, Baghdad, and the Empires of A.D. 800. New York: Ecco, 2006. ISBN 9780060797065

External links

All links retrieved October 25, 2022.


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