To look back to the early Church as a theologian and historian, and ask questions about her unity, is to enter on a long tradition, which goes back at least to the Reformation, if not to the Great Schism of 1054 itself. Once the Church had split, the various separated Christians looked back to justify their position in that tragedy. They scoured the early sources for evidence for and against episcopacy, papacy, authority confided to tradition or to Scripture alone: they questioned the form in which these early sources have come down to us - the sixteenth century saw reserves of scholarly genius poured into the problem, for instance, of the genuineness of the Ignatian correspondence, and what fired all that, apart from scholarly curiosity, was the burning question of the authenticity of episcopal authority on which Ignatius speaks so decisively. Out of that the critical discipline of patristics emerged. It was, in fact, rather later that the fourth century became the focus of the debate about the unity, authority, and identity of the Church - Newman obviously springs to mind and his Arians of the Fourth Century (London, 1833) and his Essay on the Development of Doctrine (London, 1845). Later on, the fourth century attracted the attention of scholars such as Professor H. M. Gwatkin and his Studies in Arianism (Cambridge, 1882), and Professor S. L. Greenslade and his Schism in the Early Church (London, 1953), and in quite modern times Arianism, in particular, has remained a mirror in which scholars have seen reflected the problems of the modern Church (a good example is the third part of Rowan Williams’s Arius: Heresy and Tradition [London, 1987], though there are plenty of others). Continental scholars such as Adolf von Harnack also studied the past, informed by theological perspectives derived from the present; in a different and striking way Erik Peterson turned to the fourth century to find the roots of an ideology of unity that was fuelling the murderous policies of Nazism. In all these cases the fourth century seemed to be a test case ‒ for questions of modern ecclesiology: Rome defended by development in the case of Newman, the justification for the ecumenical movement in the case of Greenslade.

Uniformity was at the heart of the Carolingian reforms, and it is apparent more than anywhere else in the liturgical reforms pursued by the Carolingians. It is logical to assume that the early Carolingian reformers’ stress on liturgical uniformity was, at least in part, a reaction to the diversity of Merovingian practice. This paper offers some preliminary observations on liturgical diversity and attitudes towards unified liturgical practices in Merovingian Gaul.

Unity and diversity form a theme which Gregory the Great addressed in his famous set of answers to Augustine of Canterbury. Augustine had asked the Pope:

To this, the Pope replied:

The early Anglo-Saxon Church felt that it possessed a special relationship with the papacy and Rome, going back (according to Bede) to the Gregorian mission of 597. Despite setbacks to this mission, unity with the Church of Rome triumphed over Irish traditions to become the keystone in the identity of the English Church. Imitation of Roman liturgical customs was a significant element in this union. In the early days of the Gregorian mission, liturgical uniformity had been unimportant, indeed Gregory specifically instructed Augustine to create a liturgy of mixed ancestry, taking the best from what he had experienced. But by the late seventh century, indifference had been overtaken by enthusiasm for the Roman chant: Bede tells us of the efforts of, for example, Benedict Biscop and Bishop Wilfrid to introduce Roman liturgical customs into their foundations. In 747, the Southumbrian Council of Clofesho decreed that the feasts of the Christian calendar and the monastic office should be performed in accordance with Roman texts and practices.

With their steady series of conquests during the eighth century, adding Alemannia, Frisia, Aquitaine, the Lombard kingdom in northern Italy, Septimania, Bavaria, Saxony, and Brittany to the Frankish heartlands in Gaul, the Carolingians created what Ganshof regarded as an unwieldy empire. Was the Carolingian Church unwieldy too? Recent work, notably that of Janet Nelson, has underlined not only the political ideologies that helped to hold the Frankish realms together, but also the practical institutions and actions of individuals in government and administration. Can the same be done for the Church? Despite the extraordinary diversity of the Carolingian world and its ecclesiastical traditions, can it be described as a unity? What sense of a ‘Frankish Church’ or of ‘Frankish ecclesiastical institutions’ can be detected in the sources?

In the spring of 999 the Emperor Otto III went on pilgrimage to the shrine of the Archangel Michael at Monte Gargano in southern Italy. His pilgrimage was not widely recorded; it was not referred to in any of the works produced in the Empire in the next half century, and only briefly mentioned in three South Italian works. But Otto’s pilgrimage was described more extensively in the eleventh-century vitae of two saints: the anonymous Greek Vita Nili and Peter Damian’s Vita Beati Romualdi. This article will make a case-study of the way in which the authors of these vitae used Otto’s pilgrimage to help construct the sanctity of their own subject, and of how far this reflects the degree of unity, and of diversity, between the Greek and Latin traditions of the Church in southern Italy in the first half of the eleventh century.

The problem could scarcely have been resolved more precisely. ‘Et tunc intravit lex romana in Sanctum Iohannem de la Penia XIo kalendas aprilis, secunda septimana quad-ragessimae, feria IIIa, hora prima et tertia fuit Tholetana, ora sexta fuit romana, anno Domini millesimo LXXIo et inde fuit servata lex romana.’

Scholarly works on the Middle Ages frequently enough mention ‘the Church in the Middle Ages’, or ‘the teaching of the Church in the Middle Ages’ without further specification, as if the reader could immediately identify the institution to which the author is referring. The authors of such works assume both that the reader readily recognizes what the author means by the phrase, but also, and perhaps more troubling, assume that there was an easily identifiable group in the Middle Ages that was ‘the Church’. Yet, when one tries actually to establish some agreement among medieval sources as to what constituted ‘the Church’ or even some agreement as to the criteria by which one could recognize a ‘the Church’, the ‘the Church’ which ought to be so solid seems to disappear into a thousand disparate factions. If, in fact, ‘the Church’ is really better described as a set of common traditions rather than as an institutional monolith, then the question of unity within ‘the Church’ would centre more on the commonality of this tradition than on the structural integrity and uniformity of belief within the institution. In short, how one understands and defines ‘the Church’ will determine the criteria by which one affirms or denies the unity of that Church. A discussion of what ‘the Church of the Middle Ages’ might be seems to be methodologically prior to any determination of the unity or disunity of Christianity in the Middle Ages. This contribution will limit itself to an exploration of some of the problems inherent in assuming that there was a ‘the Church in the Middle Ages’ and, further, that this ‘Church of the Middle Ages’ can be easily identified and defined.

On his embassy from Constantinople to the papal curia in 1339, the Greek Orthodox envoy Barlaam confided to Benedict XII his pessimistic belief that genuine union between the Churches was rendered impossible less by theological difference than by the shared history of relations between eastern and western Christendom:

In 1232 Germanus II (1223-40), the Nicaean Patriarch of Constantinople, wrote to Pope Gregory IX and to the cardinals of the Roman Church requesting discussions on the reformation of peace between the Greek and Roman Churches. In response to this request the Pope sent two English Franciscans and two French Dominicans, at least one of them proficient in Greek, as his representatives to Nicaea. After their return the friars presented a detailed account of the mission to the Pope, which was copied into the Liber Censuum. The extant documentation of the mission allows us to examine the ideas of the Greeks and Latins about unity and schism in the Church. And it shows us that there was no prospect of a union of the Churches because each had a fundamentally different conception of the nature of ecclesiastical authority.

One feature of late medieval life always strikes the modern student as most strange: the Roman Church was an institution which you could, if you had the courage, opt out of, but you did not opt in, or rather, it was assumed that you were in unless you took steps to make dissent clear. Here I would want to add that being ‘in’ included accepting the papacy. My object in this paper is to discuss aspects of this situation, to ask how the papacy was perceived before opinions were distorted by the need to accommodate the impact of Luther. There are few areas where it is more important not to write history from the Reformation backwards; between Protestant polemic and Catholic apologetic the late medieval papacy remains in need of an impartial historian. Textbooks are few and detailed studies of many aspects non-existent. In this paper I will merely try to illuminate a few questions which arise when one begins to consider what it meant to say that in the late Middle Ages all orthodox Latin Christians accepted the papacy.

On a mild spring evening in late April 1537 a group of men from the Wiltshire villages of Mere and Bledney sat drinking ‘without the door’ of a neighbour, William Brownyng. It was St Mark’s Day, traditionally a holy-day on which labour was forbidden, but recently demoted by royal command. Thomas Poole had accordingly gone about his normal work that day, but was denounced by John Tutton as a heretic ‘because he wrought on St Mark’s day’. Poole defended himself by invoking the new law, tempers flared, and Tutton imprudently aired his opinion that the moving spirit behind the new reforms, Thomas Cromwell, was, like all his ‘witholders’ a ‘stark heretic’; ‘Shall I obey the King’s commandment and it be naught?’ he asked. ‘Marry I will not.’

In principle, a distinction has often been made between the Church’s faith and its order, between what is essential to Christianity and the structure required to preserve that essence. In practice, this distinction has never been a clear-cut one, and the ideal of a unity of faith which can tolerate a diversity of rite has rarely been achieved. On the one hand, as Flacius Illyricus reminded Melanchthon in the Adiaphoristic controversy, the external organization, rites, and customs of a church are an organic expression of its beliefs: lex credendi becomes lex orandi. On the other, as Geoffrey Wainwright amongst others has noted, doctrines have frequently been formulated to reflect or to justify existing liturgical practices: lex orandi becomes lex credendi. A matter of order can become a matter of faith, and in the process what was once regarded as legitimate diversity can come to be seen as illegitimate disunity.

The Reformation in the Low Countries fascinates both church historians and general historians. Religious change and political revolution went hand in hand. The history of the Reformation is an integral part of the history of the birth of the Dutch nation. Although well-researched, its attraction is renewed with each successive historiographical fashion.

Pierre Du Moulin was the leading intellectual in the French Reformed Church in the early seventeenth century. His influence within French Protestantism rivalled and complemented that of Philippe Duplessis-Mornay, the prominent nobleman, soldier, and adviser to Henry of Navarre, the Huguenot leader who became Henry IV of France. If Duplessis-Mornay was, as he is sometimes called, the ‘Huguenot Pope’, Du Moulin, the pastor of the congregation of Protestants in Paris, was the chief cardinal. A prolific writer and a skilful speaker, Du Moulin became noted for his success as a polemicist. Yet during a period of five years, 1613–18, Du Moulin was also the chief spokesman for a plan which would unite the English, Calvinist, and Lutheran Churches. The rather startling final point of the plan called for the reunited Protestants to make a fresh approach to Rome. Du Moulin’s volte-face in 1613-18 — his sudden emergence as an irenicist — has never been satisfactorily explained.

Richard Baxter admired the qualities Giles Firmin brought to religious controversy: ‘Candor, Ingenuitie, Moderation, Love and Peace’. Firmin, Vicar of Shalford, Essex, 1648–62, argued for peace during the Interregnum, at a time when disputes fractured the churches of his county. Factions of Presbyterians and Independents still fought about the right path to religious reform, in terms dictated by polemic of the 1640s, while sects like the Quakers rattled confidence in a united Church. Firmin devised arguments that crossed party lines, to unite against sectarianism. He wrote from an unusual perspective. He had been to Massachusetts and come home. He had taken part in the colony’s bold experiment in Congregationalist church order, which inspired English Independents, but came back into parish ministry in Essex without repudiating his colonial experience. Modern historians, like seventeenth-century Presbyterians, struggle to explain why New England’s churches claimed unity with England, but acted differently. Firmin’s outlook sets contemporary polemic in a fresh light. Nowadays, he is better known for his anecdotes than for his views, because he scattered his tracts with stories about people he had known in colony and homeland. His opinions tend to escape notice. Yet Firmin used his experience in Old and New England to make a distinctive appeal for unity.