The Celtic Missionary Movement

17 Mar 2024

The 4th century push of the Ostrogoths in northeast Europe into Hun territory had led to a violent reaction on the part of the Huns, who easily overran the Ostrogoths and forced the tribes to scramble west and south into Roman lands. Stumbling efforts at peace between the Empire and the tribes led eventually to conflict. The 5th century turned out to be a very bad one for the Western Roman Empire. First, the city of Rome was sacked by the Goths in 410. Then, under Attila, the Huns solidified themselves in Eastern Europe and strengthened to the point they could raid Western Europe at will. The Vandals overran Spain and kept going, sweeping across the Mediterranean channel into North Africa where they took over Rome’s territories. Meanwhile, Christianity, which had become synonymous with the Empire in the early 300s, was in the process of dismembering itself: several Christian councils and disagreements over their results led to deep schisms with political ramifications. By 476 the Western Roman Empire had for all intents and purposes ceased to exist; and, by 480, the once-united Church had broken into four parts: Rome and Byzantium (Chalcedonian), Persia (Nestorian), Africa (Monophysite), and north and west Europe under the barbarian tribes (almost entirely Arian) (cf. Stearns 2001, Barrett 2001).

Faced with growing military threats, Rome had early on withdrew its legions from Britain. With their withdrawal, Europe for the most part seems to have turned its back on the Isles and ignored them. It was during this period that Patrick was captured by Irish slavers, then escaped and returned to begin his ministry (Cahill). He successfully established the Celtic church despite many dangers from local Irish hostile to the Gospel and intense criticism by church leaders who in many ways felt the godless Irish did not deserve a missionary (C 2001). Largely ignored by the outside world, the Irish church multiplied rapidly. Bridget (453-523) founded the monastery at Kildare and extended a missionary work throughout all Ireland; Finnian founded the renowned Clonard Abbey, and among his disciples were the “Twelve Apostles of Ireland.” Of these perhaps the most notable for our purposes is Columba, who was responsible for the evangelization of the Picts and more importantly for the founding of Iona, the famous missionary training center that sent workers all over Scotland and would send out Columbanus to Europe itself (cf. Neill, Gallagher 1995).

In the European continent itself, some order had returned to the chaos. Justinian, emperor of the Byzantine (Eastern Roman) Empire, had been successfully reconquering the Western half’s losses. European kingdoms solidified: the Frankish kingdoms in modern France and Germany, the Ostrogoths in modern Italy and the Visigoths in modern Spain. Justinian conquered the Vandals and the Ostrogoths, returning Italy and North Africa to the Byzantine-Roman fold, but was unable to completely reconquer Spain. The Avar Khanate held its At the same time the Avar Khanate (nomads from the Central Asian steppe) pushed into Eastern Europe and solidified their hold (Stearns 2001).

Yet in the midst of Justinian’s advances, “something happened” in 535: a catastrophe. Some kind of environmental disruption occurred, although experts disagree on exactly what. Some suggest it was a cometary bombardment; others believe it was the eruption of the Indonesian volcano Krakatoa (Keys). Whatever the exact cause, the results seem clear: the Earth was darkened just enough for a wave of coldness to sweep much of it. The cold brought famine, but more deadly was the way in which it cleared the path for bubonic plague to travel north into the Byzantine Empire: from 540 to 570A.D, bubonic plague decimated Europe in repeated waves: killing more adults than children, depopulating monasteries, and reducing Europe’s population by at least a half (Rosen). This was a defining turning point in the history of Europe.

In roughly the same year that the plague began, Columbanus (or Columban, the Fair Colum) was born. He came to seek the religious life, first under Sinnell of Cluaninis and then later moving on to Bangor, under Comgall. At the age of 40 (in 580 AD) he heard God’s voice calling him to preach the Gospel in foreign lands; he set sail with twelve companions and crossed into France in 585 AD—just as the plague was beginning to recede. The monasteries he founded would become a key part of the post-plague agricultural revolution that would arguably change the shape of Europe and define the future of the Christian Church by making way for the Protestant Reformation. We find this agricultural revolution at the historical intersection of the Celtic monasteries and bubonic plague: willing laborers, wide open space, and the heavy moldboard plow.

The willing laborers were, of course, Celtic missionaries and those they converted. The wide open space was brought about as a result of the depopulation of the plague. The heavy moldboard plow probably came from China, although its early history is a little vague. The plow was known to the Slavs in the fourth century and copied from them by the Goths who had the plow in Transylvania in the fourth century. The Goths likely brought it to Britain during their invasions of the fifth and sixth centuries, and either the Celts brought it back to Europe or knew it when they got there. It was a more effective plow than those that were commonly known, and could improve farming efficiency quickly enough to rapidly cause a population increase, but because of its costs could only be operated in places rich enough to provide for it: dense population settlements and monasteries. The plough required large open fields where all previous rights of ownership in specific blocks or strips were abolished: this effect was achieved by the mass depopulations of plague-ridden Europe (White 1962).

As the Celts fanned out over this post-apocalytpic world, they began cutting into the forests and plowing the fields, refarming much of Europe. Their efforts, copied by others, led to a massive population explosion (Rosen 263). In the 6th and 7th centuries, the Rhineland saw a population increase connected to the growth of open, farmed fields. By the end of the 7th century, the population was four times that of the Roman Empire (White 1962:54). The centuries-long population boom took place among a people “who paid spiritual homage to Rome but owned fealty to a usually Frankish [Germanic] king, and political power inevitably flowed north from the Mediterranean” (Rosen :265).

The structure of the Celtic Missionary Movement

Monasticism, like Christianity, originated in the East and spread through Palestine, Egypt and Syria to the West. ( Monasticism reached Gaul in the 4th century through the ministry of men such as St Martin of Tours (ca 315-397), St. John Cassian, St. Honoratus and St. Athanasios of Alexandria.

When Patrick returned to Ireland in the mid-5th century, he made thousands of converts and founded a network of clergy and monasteries. Had was often persecuted by locals in Ireland who were hostile to his work, and criticized by church leaders who felt the Irish did not deserve the Gospel, yet persevered (C 2001). Patrick traveled from place to place in missionary caravans (like “an entire village in motion”); when they stopped at a chosen site, the people from the local area would gather, converts would be made, and a chapel or church would be built and furnished. During his aposolate he consecrated 350 bishops. These bishops were attached to local kings and formed the initial network of bishoprics that would be the foundation for the future (Cahill 1995:110). For a century Christianity in Ireland ‘percolated.’ Soon enough the power structure moved from bishops to abbots and abbesses (Cahill 1995:172).

The abbots created monasteries that were centers of education (Gallagher 1995). They took children at about age 7 and taught them a regular curriculum until they were 17 (or 20 if they were to be ordained). As the influence of the monasteries spread over Ireland, at least some (though not all) of the children of every family in Ireland were thus educated in divinity, classical poetry, philosophy, Latin, Greek, science and general literature. The impact of this was that the children of the politically and economically powerful, who would grow up to be powerful themselves, would have a vested loyalty in the monastic movement–and many of those who went for education stayed to be ordained.

So powerful was this cycle that the typical monastery would have hundreds of monks active. The average monastery had perhaps 200 monks at work; some estimates suggest as many as 20,000 monks were active in any given year in Ireland (Gallagher 1995). Some would go back to secular life at the completion of their studies, but others would go on to found new monasteries and some would become apostles to foreign lands. Patrick discipled St. Brigid, who in turn had a hand in discipling St. Finian, who in turn taught the “Twelve Apostles of Ireland,” among them Columcille (St. Columba) who founded Iona, from which Columbanus headed out to his continent-shaking mission in Europe. This relational chain is just the best known and most published one—there were thousands of others. There were three major monastic training centers in Ireland: Clonard (under St Finian, with 3,000 students), Bangor (under Comgall, with 4,000 students) and Clonfert (under St Brendan the Navigator, with 3,000 students).

Three “discipleship generations” after Patrick, Columban launched his mission to Europe—as noted, just as the plagues were beginning to recede. As he and his companions entered Gual they discovered a devastated land. Europe’s population had been falling since the 4th century: demographic historians believe at least a quarter of Europe’s people had died. The area of Roman Gaul was worse off, having sunk from roughly 7.5 million to 4 million, a destruction not to be equaled until the Black Death—the return of bubonic plague a millennia later.

In 590, Pope Gregory wrote the Emperor Maurice in Byzantium to say, “All Europe is in the power of the barbarians or the heretics. The cities are overthrown, the provinces are depopulated, the soil has no longer hands to cultivate it.” During the height of the plague years, Roman taxation coupled with the invasions of European tribes and Attila’s Huns had reduced entire regions to population deserts: there were six such regions in Burgundy alone. Towns and cities had been abandoned and overgrown with forests, from the Rhine down to Switzerland. Forests had grown over the sites of former towns and cities, especially in the region of the Rhine from Belgium down to Switzerland: Luxeuil, a monastery founded by Columban which became the center of the continental monastic movement until its destruction by Islamic invaders, was built on one such overgrown city. Roman bands of criminals, soldiers, and foresters occupied the land.

In the midst of this, Columbanus’ monks began their transformative work. Pope Pius XI, while a a bishop doing research at Milan’s Ambrosiano library, wrote “the Renaissance of all Christian science and culture in France, Germany and Italy is due to the labors and zeal of Columban and his followers and successors.” The Merovingian king Sigibert at Rheims sent Columban and his 12 disciples off into this wilderness of ruined towns, and within a few years three monasteries had been established near the Vosges forest—Annegray (600 monks), Luxeiul (1,000 monks) and Fontaines (300 monks and 900 lay brothers and sisters).

They cleared the forest, farmed, gave food away and traded for craftsmen’s products. Around the monasteries, the population rapidly increased. They became centers of protection against the chaos of the times. From 590 onward, a new monastery was founded every year, and all became schools (the most important being Luxeuil). They recruited nobles as well as their serfs and slaves to become monks or students. While the Merovingian kings promoted or slaughtered each other’s children, the youth of the Burgundians and Frankish kings (often with their parents) came to study at Luxeuil, most returning to secular life with a respect for their teachers. After Columban and his Irish comrades were deported by King Theuderic, one of the trained Burgundian nobles (Walbert) took over as Abbot of Luxeuil for four decades. All the while monks from Ireland continued to pour into Gaul, and Walbert sent out missionary deployments of monks daily, many for long distances (Gallagher 1995, cf. Jonas).

Keys to the Success of the Celtic Movement

Space. The Celtic movement benefited at every point from enormous amounts of space available to them. They were willing to move into unoccupied and unwanted land that was freely available, take it over, and begin to transform it into something that was desirable.

Strong leadership and personal relationships. The Celtic movement was begun and continued by strong personalities. Fiery Patrick was able to endure great hardship, yet never shrank from engaging local political leaders on issues of importance to him, such as slavery. Men and women like Bridget of Kildare, Finnian of Clonard, Columba of Iona and Colmbanus all exhibited similar personality traits. Generations of leaders were raised by previous generations and maintained strong relationships between them and between each other.

Self-supporting and independent. The monasteries were individually self-supporting: farming the surrounding land for food and manufacturing items needed or for sale. However, the monasteries were also patronized and provided for by local rulers and village.

Field-led. Each monastery led itself, and they were tied through a strong network of personal discipling relationships to other monasteries in a decentralized grass-roots network. This field-led structure was preserved until the reunification of the Celtic and Roman Catholic Churches in 664 (C 2001).

Simplicity. Every monastery shared the same basic values (a focus on poverty, education, engagement with surrounding people, and evangelization) as well as a simple, reproducible pattern (typically, the Rule of Saint Benedict). Monasteries did not need a collection of buildings to begin with; many in fact began with simple rude huts or even in caves or fields.

Respect of the people. The Celtic monasteries were concerned for the evangelization of Ireland, yet their focus thoroughly engaged the holistic needs of the people. They became noted scholars, diplomats and teachers. Because of the way they blessed and transformed the nearby villages, they became respected and highly desired. Many were patronized by local rulers, and many local rulers sought to provide for the founding of a monastery.

Influence with leaders. Because of the respected, holy life of blessing that they lived, the monks of the monasteries had significant moral authority which led to influence with local rulers. The excommunication of a leader was not something to take lightly or ignore. As this influence grew, it led to more respect, influence, and the ability to effect change.

Ready supply of recruits. Rulers and families of influence sent their children to the Celts to be trained. Because the Celts trained children for many years (during which time the children lived in the monastery and participated in the monastic life), many of the children so trained went on to become members of a monastery. Those that did not would be favorable to the monasteries, and likely send their own children to be so trained.

Rapid multiplication. Many of those who became part of a monastery would eventually be sent out to found another monastery.

Reasons for their fall

It is difficult to ascertain exactly what led to the “end” of the Celtic missionary movement, which simply seems to fade out of published literature. Much literature covers the period from Patrick to Columbanus; some literature goes on to cover in addition men like Aidan and Gall. But after these there is little to be said. It is true that in 664 the Celtic Church was subsumed into the Catholic Church. Further, it is also true that the 8th and 9th centuries saw a marked increase in violence in the European continent. The Viking and Magyar raids were felt throughout Europe and particularly targeted the monasteries, which had become richly blessed and were tempting sources of booty. It is interesting that the Celts did not “make it” out of the European continent into Asia or Africa. Possibly, there was so much to do in Europe that it occupied them completely for the time they had. Possibly, the switch from the field-led structure of the Celtic church to the heavily centralized structure of Rome was simply too much for the the energy of even the Celts. While it seems impossible to know for certain, this latter danger seems to be one that every decentralized network should contemplate. Unfortunately it appears the Celts had little choice in the matter.


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