Pope Saint Leo I
Papacy began	29 September 440
Papacy ended	10 November 461
Predecessor	Sixtus III
Successor	Hilarius
Personal details
Birth name	Leo
Born	c. 391 or 400 Tuscany, Western Roman Empire
Died	10 November 461(461-11-10) Rome, Western Roman Empire
Sainthood
Feast day	10 November; 11 April
Venerated in	Roman Catholic and Eastern Catholic Churches, Eastern Orthodoxy, Anglicanism
Other Popes named Leo

Papal styles of Pope Leo I
Reference style	His Holiness
Spoken style	Your Holiness
Religious style	Holy Father
Posthumous style	Saint

Pope Leo I, also known as Leo the Great (c. 391 or 400 – 10 November 461) was the Bishop of Rome—the Pope—of the Catholic Church from 29 September 440 to his death on 10 November 461.

He was an Italian aristocrat, and was the first pope of the Catholic Church to have been called "the Great". He is perhaps best known for having met Attila the Hun in 452 and persuading him to turn back from his invasion of Italy. He is also a Doctor of the Church, most remembered theologically for issuing the Tome of Leo, a document which was foundational to the debates of the Ecumenical Council of Chalcedon. The Council of Chalcedon, the fourth ecumenical council, dealt primarily with Christology, and elucidated the orthodox definition of Christ's being as the hypostatic union of two natures—divine and human—united in one person, "with neither confusion nor division". The Council of Chalcedon gave rise to the first major schism in Christian history, the Monophysite schism.^[1]

Early life[link]

According to the Liber Pontificalis, he was a native of Tuscany. By 431, as a deacon, he occupied a sufficiently important position for Cyril of Alexandria to apply to him in order that Rome's influence should be thrown against the claims of Juvenal of Jerusalem to patriarchal jurisdiction over Palestine—unless this letter is addressed rather to Pope Celestine I. About the same time John Cassian dedicated to him the treatise against Nestorius written at his request. But nothing shows more plainly the confidence felt in him than his being chosen by the emperor to settle the dispute between Aëtius and Caecina Decius Aginatius Albinus, the two highest officials in Gaul.

During his absence on this mission, Pope Sixtus III died (11 August 440), and Leo was unanimously elected by the people to succeed him. On 29 September he entered upon a pontificate which was to be epoch-making for the centralization of the government of the Roman Church.

Papal authority[link]

Decree of Valentinian[link]

Leo was a significant contributor to the centralisation of spiritual authority within the Church and in reaffirming papal authority. While the bishop of Rome had always been viewed as the chief patriarch in the Western church, much of the pope's authority was delegated to local diocesan bishops. Not without serious opposition did he succeed in reasserting his authority in Gaul. Patroclus of Arles (d. 426) had received from Pope Zosimus the recognition of a subordinate primacy over the Gallican Church which was strongly asserted by his successor Hilary of Arles. An appeal from Chelidonius of Besançon gave Leo the opportunity to reassert the pope's authority over Hilary, who defended himself stoutly at Rome, refusing to recognize Leo's judicial status. Feeling that the primatial rights of the bishop of Rome were threatened, Leo appealed to the civil power for support, and obtained from Valentinian III the famous decree of 6 June 445, which recognized the primacy of the bishop of Rome based on the merits of Peter, the dignity of the city, and the legislation of the First Council of Nicaea; and provided for the forcible extradition by provincial governors of any bishop who refused to answer a summons to Rome.^[2] Faced with this decree, Hilary submitted to the pope, although under his successor, Ravennius, Leo divided the metropolitan rights between Arles and Vienne (450).

Dispute with Dioscorus of Alexandria[link]

In 445, Leo disputed with Patriarch Dioscorus, St. Cyril's successor as Patriarch of Alexandria, insisting that the ecclesiastical practice of his see should follow that of Rome on the basis that Mark the Evangelist, the disciple of Saint Peter and founder of the Alexandrian Church, could have had no other tradition than that of the prince of the apostles. This, of course, was not the position of the Copts, who saw the ancient patriarchates as equals.

Other regions[link]

Regarding Africa, the fact that the African province of Mauretania Caesariensis had been preserved to the empire and thus to the Nicene faith during the Vandal invasion, and in its isolation was disposed to rest on outside support, gave Leo an opportunity to assert his authority there, which he did decisively in regard to a number of questions of discipline.

Regarding Italy, in a letter to the bishops of Campania, Picenum, and Tuscany (443) he required the observance of all his precepts and those of his predecessors; and he sharply rebuked the bishops of Sicily (447) for their deviation from the Roman custom as to the time of baptism, requiring them to send delegates to the Roman synod to learn the proper practice.

Regarding Greece, because of the earlier line of division between the western and eastern parts of the Roman Empire, Illyria was ecclesiastically subject to Rome. Pope Innocent I had constituted the metropolitan of Thessalonica his vicar, in order to oppose the growing influence of the patriarch of Constantinople in the area. In a letter of about 446 to a successor bishop of Thessalonica, Anastasius, Leo reproached him for the way he had treated one of the metropolitan bishops subject to him; after giving various instructions about the functions entrusted to Anastasius and stressing that certain powers were reserved to the pope himself, Leo wrote: "The care of the universal Church should converge towards Peter's one seat, and nothing anywhere should be separated from its Head."^[3]

Council of Chalcedon[link]

A favorable occasion for extending the authority of Rome in the East was offered in the renewal of the Christological controversy by Eutyches, who in the beginning of the conflict appealed to Leo and took refuge with him on his condemnation by Flavian. But on receiving full information from Flavian, Leo took his side decisively. In 451 at the Council of Chalcedon, after Leo's Tome on the two natures of Christ was read out, the bishops participating in the Council cried out: "This is the faith of the fathers ... Peter has spoken thus through Leo ..."^[4]

Battling heresies[link]

An uncompromising foe of heresy, Leo found that in the diocese of Aquileia, Pelagians were received into church communion without formal repudiation of their errors; he wrote to rebuke them, making accusations of culpable negligence, and required a solemn abjuration before a synod.

Manicheans fleeing before the Vandals had come to Rome in 439 and secretly organized there; Leo learned of this around 443, and proceeded against them by holding a public debate with their representatives, burning their books^{[citation needed]}, and warning the Roman Christians against them.

Nor was his attitude less decided against the Priscillianists. Bishop Turrubius of Astorga, astonished at the spread of this sect in Spain, had addressed the other Spanish bishops on the subject, sending a copy of his letter to Leo, who took the opportunity to exercise Roman policy in Spain. He wrote an extended treatise (21 July 447), against the sect, examining its false teaching in detail, and calling for a Spanish general council to investigate whether it had any adherents in the episcopate, but this was prevented by the political circumstances of Spain.

[edit] The Tome

At the Second Council of Ephesus (commonly called the Robber Council of Ephesus) in 449, Leo's representatives delivered his famous Tome (Latin text, a letter), or statement of the faith of the Roman Church in the form of a letter addressed to Archbishop Flavian of Constantinople, which repeats, in close adherence to Augustine, the formulas of western Christology. The council did not read the letter, and paid no attention to the protests of Leo's legates, but deposed Flavian and Eusebius of Dorylaeum, who appealed to Rome. Partially due to this, the council was never recognized as ecumenical, and was later repudiated by the Council of Chalcedon.

It was presented again at the subsequent Council of Chalcedon as offering a solution to the Christological controversies still raging between East and West. This time it was read out. The acts of the council report: "After the reading of the foregoing epistle, the most reverend bishops cried out: This is the faith of the fathers, this is the faith of the Apostles. So we all believe, thus the orthodox believe. Anathema to him who does not thus believe. Peter has spoken thus through Leo. So taught the Apostles. Piously and truly did Leo teach, so taught Cyril. Everlasting be the memory of Cyril. Leo and Cyril taught the same thing, anathema to him who does not so believe. This is the true faith. Those of us who are orthodox thus believe. This is the faith of the fathers. Why were not these things read at Ephesus? These are the things Dioscorus hid away."^[5][6]

Politics of East and West[link]

Leo demanded of the emperor that an ecumenical council should be held in Italy, and in the meantime, at a Roman synod in October 449, repudiated all the decisions of the "Robber Synod". Without going into a critical examination of its dogmatic decrees, in his letters to the emperor and others he demanded the deposition of Eutyches as a Manichean and Docetic heretic.

With the death of Theodosius II in 450 and the sudden change in the Eastern situation, Anatolius, the new patriarch of Constantinople fulfilled Leo's requirements, and his Tome was everywhere read and recognized.

Leo was now no longer desirous of having a council, especially since it was not to be held in Italy. Instead, it was called to meet at Nicaea, then subsequently transferred to Chalcedon, where his legates held at least an honorary presidency, and where the bishops recognized him as the interpreter of the voice of Peter and as the head of their body, requesting of him the confirmation of their decrees.

He firmly declined to confirm their disciplinary arrangements, which seemed to allow Constantinople a practically equal authority with Rome and regarded the civil importance of a city as a determining factor in its ecclesiastical position; but he strongly supported its dogmatic decrees, especially when, after the accession of Leo I the Thracian (457), there seemed to be a disposition toward compromise with the Eutychians.

He succeeded in having an imperial patriarch, and not the Oriental Orthodox Pope Timotheus Aelurus, chosen as Coptic Orthodox Pope of Alexandria on the murder of Greek Patriarch Proterius of Alexandria.

Raphael's The Meeting between Leo the Great and Attila depicts Leo, escorted by Saint Peter and Saint Paul, meeting with the Hun king outside Rome

The approaching collapse of the Western Empire gave Leo a further opportunity to appear as the representative of lawful authority.

Leo and Attila[link]

In 452, Attila invaded Italy, sacking cities such as Aquileia and heading for Rome. He allegedly demanded that the sister of the reigning Emperor Valentinian III be sent to him with a dowry. In response, the Emperor sent three envoys to negotiate with Attila: Gennadius Avienus, one of the consuls of 450, Memmius Aemilius Trygetius, the former urban prefect, and Leo. We do not know much about the negotiations, but Attila withdrew. This outcome has been debated among historians for centuries. A large sum of gold that the pope possibly carried with him or Attila´s logistical and strategic concerns may have been the true reasons for Attila's mercy. His army was probably laden with booty from plunder; a plague broke out in northern Italy; food shortages may also be responsible for Attila´s withdrawal, as well as military actions of the Eastern Emperor Marcianus on the Danube frontier. Furthermore, we know next to nothing of the whereabouts of Aëtius at that time; perhaps Attila or his warriors felt endangered by their arch-enemy from the Catalaunian plains. The pope's plea for mercy may well have merely served as an honorable excuse for not continuing on and sacking the Roman capital.

John B. Bury remarked:
"The fact of the embassy cannot be doubted. The distinguished ambassadors visited the Hun's camp near the south shore of Lake Garda. It is also certain that Attila suddenly retreated. But we are at a loss to know what considerations were offered him to induce him to depart. It is unreasonable to suppose that this heathen king would have cared for the thunders or persuasions of the Church. The Emperor refused to surrender Honoria, and it is not recorded that money was paid. A trustworthy chronicle hands down another account which does not conflict with the fact that an embassy was sent, but evidently furnishes the true reasons which moved Attila to receive it favourably. Plague broke out in the barbarian host and their food ran short, and at the same time troops arrived from the east, sent by Marcian to the aid of Italy. If his host was suffering from pestilence, and if troops arrived from the east, we can understand that Attila was forced to withdraw. But whatever terms were arranged, he did not pretend that they meant a permanent peace. The question of Honoria was left unsettled, and he threatened that he would come again and do worse things in Italy unless she were given up with the due portion of the Imperial possessions."^[7]

However, Christian historians celebrated Leo's actions, giving him all the credit for this successful embassy. According to Prosper of Aquitaine, Attila was so impressed by Leo that he withdrew.^[8] Jordanes says that Attila was afraid of sharing the fate of the Visigothic king Alaric, who died shortly after sacking Rome in 410.^[9] Paul the Deacon, in the late 8th century, relates that an enormously huge man dressed in priestly robes and armed with a naked sword, visible only to Attila, threatened him and his army with death during his discourse with Leo, and this prompted Attila to submit to his request.^[10] Unfortunately Leo's intercession could not prevent the sack of the city by the Vandals in 455, but murder and arson were repressed by his influence. He died probably on 10 November 461.

On Dignity and Equality[link]

In his Nativitate Domini, in the Christmas Day sermon "Christian, Remember your Dignity" Leo appears to articulate a fundamental and inclusive human dignity and equality: The saint, the sinner, and the unbeliever are all equal as sinners, and none is excluded in the call to "happiness":

Our Saviour, dearly-beloved, was born today: let us be glad. For there is no proper place for sadness, when we keep the birthday of the Life, which destroys the fear of mortality and brings to us the joy of promised eternity. No one is kept from sharing in this happiness. There is for all one common measure of joy, because as our Lord the destroyer of sin and death finds none free from charge, so is He come to free us all. Let the saint exult in that he draws near to victory. Let the sinner be glad in that he is invited to pardon. Let the gentile take courage in that he is called to life.^[11]

Leo's significance[link]

The significance of Leo's pontificate lies in his assertion of the universal jurisdiction of the Roman bishop, as expressed in his letters, and still more in his 96 extant orations. This assertion is commonly referred to as the doctrine of Petrine supremacy.

According to Leo and several Church Fathers, as well as certain interpretations of the Scriptures, the Church is built upon Peter, in pursuance of the promise of Matthew 16:16–19. Peter participates in everything which is Christ's; what the other apostles have in common with him they have through him. What is true of Peter is true also of his successors. Every other bishop is charged with the care of his particular flock, the Roman pontiff with that of the whole Church. Other bishops are his assistants in this great task. In Leo's eyes the decrees of the Council of Chalcedon acquired their validity from his confirmation.

Leo's letters and sermons reflect the many aspects of his career and personality, including his great personal influence for good, and are invaluable historical sources. His rhythmic prose style, called cursus leonicus, influenced ecclesiastical language for centuries.

The Roman Catholic Church marks 10 November as the feast day of Saint Leo, given in the Martyrologium Hieronymianum and the 8th-century Calendar of Saint Willibrord as the date of his death and entry to heaven. His feast was once celebrated in Rome on 28 June, the anniversary of the placing of his relics in Saint Peter's Basilica, but in the 12th century the Gallican Rite feast of 11 April was admitted to the General Roman Calendar, which maintained that date until 1969.^[12] Some traditionalist Catholics continue to observe pre-1970 versions of that calendar.

The Eastern Catholic Churches as well as the Eastern Orthodox Church celebrate Saint Leo on 18 February.

Burial[link]

Leo was originally buried in his own monument. However, some years after his death, his remains were put into a tomb that contained the first four Pope Leos. In the 18th century Leo the Great's relics were separated from those of the other Leo's and he was given his own chapel.^[13]

Hymns[link]

Troparion (Tone 3)

You were the Church's instrument

in strengthening the teaching of true doctrine;

you shone forth from the West like a sun dispelling the errors of the heretics.

Righteous Leo, entreat Christ God to grant us His great mercy.

Troparion (Tone 8)

O Champion of Orthodoxy, and teacher of holiness,

The enlightenment of the universe and the inspired glory of true believers.

O most wise Father Leo, your teachings are as music of the Holy Spirit for us!

Pray that Christ our God may save our souls!

Kontakion (Tone 3)

Seated upon the throne of the priesthood, glorious Leo,

you shut the mouths of the spiritual lions.

With divinely inspired teachings of the honored Trinity,

you shed the light of the knowledge of God up-on your flock.

Therefore, you are glorified as a divine initiate of the grace of God.

See also[link]

Saints portal

• List of 10 longest-reigning popes

References[link]

Wikisource has original works written by or about: Leo I

Wikimedia Commons has media related to: Leo I Magnus

External links[link]

• "St. Leo the Great, Pope", Butler's Lives of the Saints
• St Leo of Rome Orthodox Synaxarion (18 February)
• Early Church Fathers: Leo the Great

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The LEO I (Lyons Electronic Office I) was the first computer used for commercial business applications. Overseen by Oliver Standingford and Raymond Thompson of J. Lyons and Co., and modelled closely on the Cambridge EDSAC, LEO I ran its first business application in 1951. In 1954 Lyons formed LEO Computers Ltd to market LEO I and its successors LEO II and LEO III to other companies. LEO Computers eventually became part of English Electric Company (EELM) and then International Computers Limited (ICL) and ultimately Fujitsu. LEO series computers were still in use until 1981.^{[citation needed]}

Origins and initial design[link]

J. Lyons and Co., one of the UK's leading catering and food manufacturing companies in the first half of the 20th century, sent two of its senior managers, Oliver Standingford and Raymond Thompson, to the USA in 1947 to look at new business methods developed during the Second World War. During their visit they met Herman Goldstine, one of the original developers of ENIAC, the first general-purpose electronic computer (although it had no stored program). Standingford and Thompson saw the potential of computers to help solve the problem of administering a major business enterprise. They also learned from Goldstine that, back in the UK, Douglas Hartree and Maurice Wilkes were actually building another such machine, the pioneering EDSAC computer, at the University of Cambridge.^[1]

On their return to the UK, Standingford and Thompson visited Hartree and Wilkes in Cambridge, and were favourably impressed with their technical expertise and vision. Hartree and Wilkes estimated that EDSAC was twelve to eighteen months from completion, but said that this timeline could be shortened if additional funding were available. Standingford and Thompson wrote a report to the Lyons' Board recommending that Lyons should acquire or build a computer to meet their business needs. The board agreed that, as a first step, Lyons would provide Hartree and Wilkes with £3,000 funding for the EDSAC project, and would also provide them with the services of a Lyons electrical engineer, Ernest Lenaerts. EDSAC was completed and ran its first program in May 1949.^[2]

Following the successful completion of EDSAC, the Lyons' board agreed to start the construction of their own machine, expanding on the EDSAC design. The Lyons machine was christened Lyons Electronic Office, or LEO. On the recommendation of Wilkes, Lyons recruited John Pinkerton, a radar engineer and research student at Cambridge, as team leader for the project. Lenaerts returned to Lyons to work on the project, and Wilkes provided training for Lyons' engineer Derek Hemy, who would be responsible for writing LEO's programs. The first business application to be run on LEO was Bakery Valuations. This was initially run as a test program on 5 September 1951, and LEO took over Bakery Valuations calculations completely on 29 November 1951.^[3]

Technical description[link]

LEO I's clock speed was 500 Hz, with most instructions taking about 1.5 ms to execute. ^{[4][citation needed]} To be useful for business applications, the computer had to be able to handle a number of data streams, input and output, simultaneously. Therefore, its chief designer, Dr. John Pinkerton, designed the machine to have multiple input/output buffers. In the first instance, these were linked to fast paper tape readers and punches, fast punched card readers and punches, and a 100 line a minute tabulator. Later, other devices, including magnetic tape, were added. Its ultrasonic delay line memory based on tanks of mercury, with 2K (2048) 35-bit words (i.e., 8¾ K bytes), was four times as large as that of EDSAC. The systems analysis was carried out by David Caminer.^[5]

Applications and successors[link]

Lyons used LEO I initially for valuation jobs, but its role was extended to include payroll, inventory, and so on. One of its early tasks was the elaboration of daily orders which were phoned in every afternoon by the shops and used to calculate the overnight production requirements, assembly instructions, delivery schedules, invoices, costings, and management reports. This, arguably, was the first instance of an integrated management information system plus a computerised call centre. The LEO project was also a pioneer in outsourcing: in 1956, Lyons started doing the payroll calculations for Ford UK and others on the LEO I machine. The success of this led to the company dedicating one of its LEO II machines to bureau services. Later, the system was used for scientific computations, as well. Met Office office staff used a LEO I before the Met Office bought its own computer, a Ferranti Mercury, in 1959.^[6]

A circuit board from a LEO III computer

In 1954, with the decision to proceed with LEO II and interest from other commercial companies, Lyons formed LEO Computers Ltd. The first LEO III was completed in 1961. This was a solid-state machine with a 13.2Failed to parse (Missing texvc executable; please see math/README to configure.): \mu s cycle time ferrite core memory. It was micro-programmed and was controlled by a multi-tasking operating system. In 1963, LEO Computers Ltd was merged into English Electric Company and this led to the breaking up of the team that had inspired LEO computers. English Electric Company continued to build the LEO III, and went on to build the faster LEO 360 and even faster LEO 326 models, which had been designed by the LEO team before the takeover. All LEO IIIs allowed concurrent running of as many as 12 application programs through the "Master program" operating system. Some, primarily producing telephone bills, were still in commercial use with GPO Telephones, forerunner of British Telecom, until 1981, which remained usable through parts cannibalised from redundant LEOs purchased by the GPO.^{[citation needed]}

Users of LEO computers programmed in two coding languages: Intercode, a low-level assembler type language; and CLEO (acronym: Clear Language for Expressing Orders), the COBOL equivalent.^{[citation needed]}

Many users^[who?] fondly remember the LEO III and enthuse about some of its quirkier features, such as having a loudspeaker connected to the central processor which enabled operators to tell whether a program was looping by the distinctive sound it made.^{[citation needed]} Many intermittent faults were due to dry joints and could be temporarily fixed by briskly strumming the card handles!

English Electric LEO Computers Ltd or English Electric Leo Marconi (EELM) eventually merged with International Computers and Tabulators (ICT) and others to form International Computers Limited (ICL) in 1968. In the 1980s, there were still ICL 2900 mainframes emulating LEO programs.^[7]

References[link]

Bibliography[link]

Books[link]

• Bird, P.J. (1994). LEO: The First Business Computer. Wokingham: Hasler Publishing Co. ISBN 0-9521651-0-4.
• Caminer, D. T.; Aris, J. B., Hermon, P. M., Land, F. F. (1998). LEO: the incredible story of the world’s first business computer. McGraw-Hill. ISBN 0-07-009501-9. 
• Campbell-Kelly, M., (1989). ICL: A Business and Technical History. Oxford: Clarendon Press.
• Caminer, D.T., Aris, J.B.B., Hermon, P.M.R., Land, F.F. (1996). User-Driven Innovation: The World’s First Business Computer. London: McGraw-Hill. ISBN 0-07-009501-9.
• Carmichael, H., editor (1996). An ICL Anthology, Chapter 6: LEO, Laidlaw Hicks, Surbiton, UK.
• Ferry, G. (2004). A Computer Called LEO: Lyons Tea Shops and the World's First Office Computer. Hammersmith: Harper Perennial. ISBN 1-84115-186-6.
• Hally, M. (2005). Electronic Brains: stories from the dawn of the computer age. Washington:Joseph Henry Press. Chapter 5: LEO the Lyons Computer. ISBN 0-309-09630-8.
• Land, F.F., (1997). LEO, the First Business Computer: A Personal Experience. In Glass, R.L., editor. In the Beginning: Recollections of Software Pioneers, pages 134–153. IEEE Computer Society, Los Alamitos, CA.
• PEP, (1957). Three Case Studies in Automation, PEP, London.
• Simmons, J.R.M., (1962). LEO and the Managers, MacDonald, London.

Articles[link]

• Aris, J.B.B. (1996). "Systems Design — Then and Now". Resurrection, Summer issue 1996.
• Land, F.F. (1996). "Systems Analysis for Business Applications". Resurrection, Summer issue 1996.
• Aris, J.B.B. (2000). "Inventing Systems Engineering". IEEE Annals of the History of Computing, Vol. 22, No. 3, July–September, pp. 4–15
• Land, F.F. (2000). "The First Business Computer: A Case Study in User-Driven Automation". IEEE Annals of the History of Computing, Vol. 22, No. 3, July–September, pp. 16–26.
• Caminer, D.T. (1958), "...And How to Avoid Them". The Computer Journal, Vol. 1, No. 1.
• Caminer, D.T. (1997). "LEO and its Applications: The Beginning of Business Computing". The Computer Journal, Vol. 40, No. 10.
• Caminer, D.T. (2003). "Behind the Curtain at LEO: A Personal Reminiscence". IEEE Annals of the History of Computing, Vol. 25, No. 2, April–June, pp3–13.
• Hendry, J. (1988). "The Teashop Computer Manufacturer: J. Lyons". Business History, Vol. 29, No. 8, pp. 73–102.
• Land, Frank (1999). "A Historical Analysis of Implementing IS at J. Lyons." In Currie, W.G.; Galliers, R.D., editors. Rethinking Management Information Systems, pp. 310–325. Oxford University Press.

External links[link]

• Oral history interview with John M. M. Pinkerton, Charles Babbage Institute, University of Minnesota. Pinkerton describes his work on the Leo computers. In this context he discusses the British computer firms J. Lyons and Company, English Electric, and International Computers Ltd.
• About LEO — From Business Computing: the Second 50 Years, The Guildhall conference for business leaders, 2001
• J. Lyons & Co.: LEO Computers. Extract from Peter Bird's LEO — The First Business Computer (2002); at David Lawrence's Lyons website
• LEO Computers Society. Accessed 2007-08-31
• BBC Science - Electronic Brains BBC Radio 4 Series about early computers, Programme 1 is about LEO
• A computer called LEO: Lyons Teashops and the world's first office computer A standard work on the development of LEO
• Obituary of Caminer Daily Telegraph, 24 June 2008

Leo XIII
File:PapaleoXIII (1).jpg Leo XIII
Papacy began	20 February 1878
Papacy ended	20 July 1903
Predecessor	Pius IX
Successor	Pius X
Orders
Ordination	31 December 1837 by Carlo Odescalchi
Consecration	19 February 1843 by Luigi Emmanuele Nicolò Lambruschini
Created Cardinal	19 December 1853
Personal details
Birth name	Vincenzo Gioacchino Raffaele Luigi Pecci
Born	2 March 1810 Carpineto Romano, département of Rome, French Empire
Died	20 July 1903 (aged 93) Apostolic Palace, Rome, Kingdom of Italy
Coat of arms

Papal styles of Pope Leo XIII
Reference style	His Holiness
Spoken style	Your Holiness
Religious style	Holy Father
Posthumous style	None

Pope Leo XIII (2 March 1810 – 20 July 1903), born Vincenzo Gioacchino Raffaele Luigi Pecci to an Italian comital family, was the 256th Pope of the Roman Catholic Church, reigning from 1878 to 1903. He was the oldest pope (reigning until the age of 93), and had the third longest pontificate, behind his immediate predecessor Pius IX and John Paul II.

He is known for intellectualism, the development of social teachings with his encyclical Rerum Novarum and his attempts to define the position of the Church with regard to modern thinking. He influenced Roman Catholic Mariology and promoted both the rosary and the scapular. He issued a record eleven encyclicals on the rosary, approved two new Marian scapulars and was the first Pope to fully embrace the concept of Mary as mediatrix.

Early life[link]

Born in Carpineto Romano, near Rome, he was the sixth of the seven sons of Count Ludovico Pecci and his wife Anna Prosperi Buzzi. Until 1818 he lived at home with his family, "in which religion counted as the highest grace on earth, as through her, salvation can be earned for all eternity".^[1] Together with his brother he studied in the Jesuit College in Viterbo, where he stayed until 1824.^[2] He enjoyed the Latin language and was known to write his own Latin poems at the age of eleven.

In 1824 he and his older brother Giuseppe were called to Rome where their mother was dying. Count Pecci wanted his children near him after the loss of his wife, and so they stayed with him in Rome, attending the Jesuit Collegium Romanum. In 1828, Giuseppe entered the Jesuit order, while Vincenzo decided in favour of secular clergy.^[3]

He studied at the Academia dei Nobili, mainly diplomacy and law. In 1834 he gave a student presentation, attended by several cardinals, on papal judgements. For his presentation he received awards for academic excellence, and gained the attention of Vatican officials.^[4] Cardinal Secretary of State Luigi Lambruschini introduced him to Vatican congregations and to Pope Gregory XVI, who appointed Pecci on 14 February 1837, as personal prelate even before he was ordained priest on 31 December 1837, by the Vicar of Rome. He celebrated his first mass together with his priest brother Giuseppe.^[5] He received his doctorate in theology in 1836 and doctorates of civil and Canon Law in Rome also.

Provincial administrator[link]

Shortly thereafter, Gregory XVI appointed Pecci as legate (provincial administrator) to Benevento. The smallest of papal provinces, Benevento included about 20,000 people.

The main problems facing Pecci were a decaying local economy, insecurity because of widespread bandits, and pervasive Mafia structures, who often were allied with aristocratic families. Pecci arrested the most powerful aristocrat in Benevento, and his troops captured others, who were either killed or imprisoned by him. With the public order restored, he turned to the economy and a reform of the tax system to stimulate trade with neighboring provinces.^[6]

Upon completion of the tax reforms, Gregory XVI appointed Pecci to be administrator of Spoleto, a province with 100,000, and then Perugia with 200,000 inhabitants.

His immediate concern was to prepare the province for a papal visitation in the same year. Pope Gregory visited hospitals and educational institutions for several days, asking for advice and listing questions. The fight against corruption continued in Perugia, where Pecci himself investigated several incidents. When it was claimed that a bakery was selling bread below the prescribed pound weight, he personally went there, had all bread weighed, and confiscated it if below legal weight. The confiscated bread was distributed to the poor.^[7]

Nuncio to Belgium[link]

In 1843, Pecci, only thirty-four years old, was appointed Apostolic Nuncio to Belgium, a position which guaranteed the Cardinal's hat after completion of the tour.

On 27 April 1843, Pope Gregory XVI appointed Pecci Archbishop of Damiette and asked his Cardinal Secretary of State Lambruschini to consecrate him. Pecci developed excellent relations with the royal family and used the location to visit neighbouring Germany, where he was particularly interested in the resumed construction of the Cologne Cathedral.

Upon his initiative, a Belgian College in Rome was opened in 1844, where 100 years later, in 1946, Pope John Paul II would begin his Roman studies. He spent several weeks in England with Bishop Nicholas Wiseman, carefully reviewing the condition of the Catholic Church in that country.^[8]

In Belgium, the school question was then sharply debated between the Catholic majority and the Liberal minority. Pecci encouraged the struggle for Catholic schools, yet he was able to win the good will of the Court, not only of the pious Queen Louise, but also of King Leopold I, strongly Liberal in his views. The new nuncio succeeded in uniting the Catholics.

Archbishop of Perugia[link]

Papal assistant[link]

Pecci was named papal assistant in 1843. He first achieved note as the popular and successful Bishop of Perugia from 1846 to 1877. In 1847, Pope Pius IX issued unlimited freedom for the press, which, after many years of restrictions, was highly welcomed and popular.^[9] In the following year, in 1848, revolutionary movements developed throughout Western Europe including France, Germany and Italy.

Pecci, who was highly popular in the first years of his episcopate, became now the object of attacks, both in the media and in his residence.^[10] The papal minister Rossi was assassinated and Pope Pius IX had to flee to Gaeta. In the following months, Austrian, French and Spanish troops reversed the revolutionary gains, but at a price for Pecci and the Catholic Church, who could not regain their former popularity.

Provincial council[link]

Pecci called a provincial council, in order to reform the religious life in his dioceses. He invested in the enlargement of the seminary for future priests and in new and prominent professors, preferably Thomists. He called on his brother Giuseppe Pecci, a noted Thomist scholar, to resign his professorship in Rome and teach instead in Perugia.^[11] His own residence was next to the seminary, which aided daily contacts of the students with the de-facto head of the seminary, Archbishop Pecci.

Charitable activities[link]

Pecci developed several activities in support of Catholic charities: He founded homes for homeless boys and girls, and for elderly women. Throughout his dioceses he opened branches of a Bank, Monte de Pieta, which focused on low-income people and provided low interest loans.^[12] He created soup-kitchens, which were run by the Capuchins. In the consistory of 19 December 1853, he was elevated to the College of Cardinals, as Cardinal-Priest of S. Crisogono. In light of continuing earthquakes and floods, he donated all resources for festivities to the victims. Much of the public attention turned on the conflict between the Papal States and Italian nationalism, aiming at these states' annihilation so as to achieve the Unification of Italy.

Defence of the papacy[link]

Pecci defended the papacy and its claims. When Italian authorities expropriated convents and monasteries of Catholic orders, turning them into administration or military buildings, Cardinal Pecci protested but acted moderately. When the Italian state took over Catholic schools, Pecci, fearing for his theological seminary, simply added all secular topics from other schools and opened the seminary to non-theologians.^[13] The new government in addition to the expropriations levied taxes on the Church and issued legislation, according to which all Episcopal or papal utterances are to be approved by the government before their publication.^[14]

Organizing the First Vatican Council[link]

Pope Pius IX announced an ecumenical council, which became known as the First Vatican Council, to take place in the Vatican on 8 December 1869, Pecci was likely to be well informed, since his brother Giuseppe had been named by the Pope to be one of the persons to prepare this event.

In his last years in Perugia, Pecci several times addressed the role of the Church in modern society. Pecci defined the Church as the mother of material civilization, because the Church upholds human dignity of working people, opposes the excesses of industrialization and developed large scale charities for the needy.^[15]

Camerlengo[link]

In August 1877, on the death of Cardinal Filippo de Angelis, Pope Pius IX appointed him Camerlengo, so that he was obliged to reside in Rome. Pope Pius died on 7 February 1878, and during his closing years the Liberal press had often insinuated that the Italian Government should take a hand in the conclave and occupy the Vatican. However the Russo-Turkish War and the sudden death of Victor Emmanuel II (9 January 1878) distracted the attention of the government. The conclave proceeded as usual, and on the third ballot Cardinal Pecci was elected by forty-four votes out of sixty-one.

Papacy[link]

Part of a series of articles on Social Teachings of the Popes

Pope Leo XIII Rerum Novarum Pope Pius XI Quadragesimo Anno Pope Pius XII Social teachings Pope John XXIII Mater et Magistra Pacem in Terris Vatican II Dignitatis Humanae Gaudium et Spes Pope Paul VI Populorum progressio Pope John Paul II Centesimus Annus Laborem Exercens Sollicitudo Rei Socialis Pope Benedict XVI Caritas in Veritate Deus Caritas Est General Social Teachings of the Popes Catholic social teaching Subsidiarity Solidarity (Catholic theology) Tranquillitas Ordinis

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Photogram of the 1896 film Sua Santitá papa Leone XIII, the first time a Pope appeared on a movie.

As soon as he was elected to the papacy, Leo XIII worked to encourage understanding between the Church and the modern world. When he firmly re-asserted the scholastic doctrine that science and religion co-exist, he required the study of Thomas Aquinas^[16] and opened the Vatican Secret Archives to qualified researchers, among whom was the noted historian of the Papacy Ludwig von Pastor. He also re-founded the Vatican Observatory "so that everyone might see clearly that the Church and her Pastors are not opposed to true and solid science, whether human or divine, but that they embrace it, encourage it, and promote it with the fullest possible devotion."^[17]

Leo XIII was the first Pope of whom a sound recording was made. The recording can be found on a compact disc of Alessandro Moreschi's singing; a recording of his performance of the Ave Maria is available on the web. He was also the first Pope to be filmed on the motion picture camera. He was filmed by its inventor, W. K. Dickson, and blessed the camera while being filmed.^[18][19] Since he was born in 1810, he also became the earliest-born notable person who was filmed.^{[citation needed]}

Leo XIII brought normality back to the Church after the tumultuous years of Pius IX. Leo's intellectual and diplomatic skills helped regain much of the prestige lost with the fall of the Papal States. He tried to reconcile the Church with the working class, particularly by dealing with the social changes that were sweeping Europe. The new economic order had resulted in the growth of an impoverished working class, with increasing anti-clerical and socialist sympathies. Leo helped reverse this trend.

While Leo was no radical in either theology or politics, his papacy did move the Church back to the mainstream of European life. Considered a great diplomat, he managed to improve relations with Russia, Prussia, Germany, France, England and other countries.

Pope Leo XIII was able to reach several agreements in 1896, which resulted in better conditions for the faithful and additional appointments of bishops. During the Fifth cholera pandemic in 1891 he ordered the construction of a hospice inside the Vatican. That building would be torn down in 1996 to make way for construction of the Domus Sanctae Marthae.^[20]

His favorite poets were Virgil and Dante.^[21]

Foreign relations[link]

Russia[link]

Pope Leo XIII began his pontificate with a friendly letter to Tzar Alexander II, in which he reminded the Russian monarch of the millions of Catholics living in his empire, who would like to be good Russian subjects, provided their dignity is respected.

After the assassination of Alexander II, the Pope sent a high ranking representative to the coronation of his successor. Alexander III was grateful and asked for all religious forces to unify. He asked the Pope to ensure that his bishops abstain from political agitation. Relations improved further, when Pope Leo XIII, due to Italian considerations, distanced the Vatican from the Rome-Vienna-Berlin alliance and helped to facilitate a rapprochement between Paris and St. Petersburg.

Germany[link]

Under Otto von Bismarck, the anti-Catholic Kulturkampf in Prussia led to massive reprisals against the Church. Under Leo, compromises were informally reached and the anti-Catholic attacks subsided.^[22]

The Centre Party in Germany represented Catholic interests and was a positive force for social change. It was encouraged by Leo's support for social welfare legislation and the rights of working people. Leo's forward-looking approach encouraged Catholic Action in other European countries where the social teachings of the Church were incorporated into the agenda of Catholic parties, particularly the Christian democratic parties, which became an acceptable alternative to socialist parties. Leo's social teachings were reiterated throughout the 20th century by his successors.

In his Memoirs^[23] Kaiser Wilhelm II discussed the "friendly, trustful relationship that existed between me and Pope Leo XIII." During Wilhelm's third visit to Leo: "It was of interest to me that the Pope said on this occasion that Germany must be the sword of the Catholic Church. I remarked that the old Roman Empire of the German nation no longer existed, and that conditions had changed. But he adhered to his words."

France[link]

Leo XIII was the first Pope to come out strongly in favour of the French Republic, upsetting many French monarchists.

Italy[link]

However, in light of a hostile anti-Catholic climate in Italy, he continued the policies of Pius IX towards Italy, without major modifications.^[24] In his relations with the Italian state, Leo XIII continued the Papacy's self-imposed incarceration in the Vatican stance, and continued to insist that Italian Catholics should not vote in Italian elections or hold elected office. In his first consistory in 1879 he elevated his older brother Giuseppe to the cardinalate. He had to defend the freedom of the Church against what Catholics considered Italian persecutions and attacks in the area of education, expropriation and violation of Catholic Churches, legal measures against the Church and brutal attacks, culminating in anticlerical groups attempting to throw the body of the deceased Pope Pius IX into the Tiber river on 13 July 1881.^[25] The Pope even considered moving his residence to Trieste or Salzburg, two cities in Austria, an idea which the Austrian monarch Franz Josef I gently rejected.^[26]

United Kingdom[link]

Among the activities of Leo XIII that were important for the English-speaking world, he restored the Scottish hierarchy in 1878. In the following year, on 12 May 1879, raised to the rank of cardinal the convert clergyman John Henry Newman, who was to be beatified by Pope Benedict XVI in 2010. In British India, too, Leo established a Catholic hierarchy in 1886, and regulated some long-standing conflicts with the Portuguese authorities. Of outstanding significance, not least for the English-speaking world, was Leo's encyclical Apostolicae Curae on the invalidity of the Anglican orders, published in 1896.

United States[link]

In 1889, Pope Leo XIII authorized the founding of The Catholic University of America in Washington, D.C., and granted her Papal degrees in theology

The United States at many moments in time attracted the attention and admiration of Pope Leo. He confirmed the decrees of the Third Plenary Council of Baltimore (1884), and raised James Gibbons, archbishop of that city, to the cardinalate in 1886.

American newspapers criticized Pope Leo because they claimed that he was attempting to gain control of American public schools. One cartoonist drew Leo as a fox unable to reach grapes that were labeled for American schools; the caption read "Sour grapes!"

Brazil[link]

Pope Leo is also remembered for the First Plenary Council of Latin America held at Rome in 1899, and his encyclical of 1888 to the bishops of Brazil on the abolition of slavery.

Peru[link]

His role in South America will also be remembered, especially the pontifical benediction extended over Chilean troops on the eve of the Battle of Chorrillos during the War of the Pacific in January 1881. The Chilean soldiers thus blessed then looted the cities of Chorrillos and Barranco, including the churches, and their Chaplains headed the robbery at the Biblioteca Nacional del Perú, where the soldiers ransacked various items along with much capital, and Chilean Priests coveted rare and ancient editions of the Bible that were stored there.^[27] Despite this, one year later Chilean President Domingo Santa Marìa issued the Laicist Laws, which separated the Church from the State, this being considered a slap in the face for the Papacy.

Evangelization[link]

Pope Leo sanctioned the missions to eastern African.^{[citation needed]} In 1879 Catholic missionaries associated with the White Father Congregation (Society of the Missionaries of Africa) came to Uganda and others went to Tanganyika (present day Tanzania) and Rwanda.

Theology[link]

Giuseppe Pecci in 1872. At the urgent requests of the College of Cardinals, Leo XIII in 1879 elevated his brother, Giuseppe Pecci, a Jesuit and prominent Thomist theologian, into their ranks.^[28]

The pontificate of Leo XIII was theologically influenced by the First Vatican Council (1869–1870), which had ended only eight years earlier. Leo issued some 46 apostolic letters and encyclicals dealing with central issues in the areas of marriage and family and state and society.

Thomism[link]

As Pope, he used all his authority for a revival of Thomism, the theology of Thomas Aquinas. On 4 August 1879, Leo promulgated the encyclical Aeterni Patris (“Eternal Father”) which, more than any other single document, provided a charter for the revival of Thomism—the medieval theological system based on the thought of Aquinas—as the official philosophical and theological system of the Roman Catholic Church. It was to be normative not only in the training of priests at church seminaries but also in the education of the laity at universities.

Consecrations[link]

Leo XIII performed a number of consecrations, at times entering new theological territory. His consecration of the entire world to the Sacred Heart of Jesus presented theological challenges in consecrating non-Christians. Since about 1850, various congregations and States had consecrated themselves to the Sacred Heart, and, in 1875, this consecration was made throughout the Catholic world.

Scriptures[link]

In his 1893 encyclical Providentissimus Deus, he described the importance of scriptures for theological study. It was an important encyclical for Catholic theology and its relation to the Bible, as Pope Pius XII pointed out fifty years later in his encyclical Divino Afflante Spiritu.^[29]

Ecumenical efforts[link]

Pope Leo XIII fostered ecumenical relations leading to the reintegration of the Armenian Church into the Catholic Church in 1879. He opposed efforts to Latinize the Eastern Rite Churches, stating that they constitute a most valuable ancient tradition and symbol of the divine unity of the Catholic Church.