Probing the intersection of faith and politics

Christendom:
The Triumph of a Religion

Peter Heather
Allen Lane, 2022.

How did it happen that in the waning days of the Roman Empire, a small, often persecuted religious movement that had spent three centuries on the fringes of society, suddenly swept through the Empire’s population, institutions, and power structures until, in Gibbon’s famous words, it “finally erected the triumphant banner of the Cross on the ruins of Capitol.” In Christendom: The Triumph of a Religion, Peter Heather, a professor at King’s College London, argues that the spread of Christianity as a religion cannot be separated from the rise of the confessional polity that later became the medieval concept of Christendom.

Christendom is a detailed and in-depth plunge into these parallel stories, starting with the “conversion” of Constantine in 312, when Christianity overtly entered the corridors of power in the Roman Empire; and ending with the Fourth Lateran Council in 1215, where a specific concept of Christian belief and practice was adopted that could now be enforced by religious and political authorities. Thus was medieval Christendom born: “A huge swath of territory – stretching from Spain to Scandinavia, Iceland to Poland – was brought to a striking and utterly unprecedented degree of religious uniformity under the authority of the Roman Papacy.”

A political and contingent movement

Two broad themes permeate Heather’s story. First, Christianity’s rise was, to a considerable degree, a political phenomenon. Its immediate successes in the reign of Constantine and his heirs were due to the new power dynamic under which Christian adherence (outwardly if not inwardly) was crucial to social advancement and achieving positions of power and influence in the Empire and its institutions. The result was a new, imperial Christianity, whose continuation and propagation was inextricably linked to its ongoing association with political power. It was an elite movement, absorbing first the Roman Empire’s cultural and political heights and later spreading into the leaders of the barbarian tribes and later Kingdoms that replaced the empire or established themselves beyond it. And along the way Christianity itself was changed – “Romanized” according to Heather – with the Jesus movement accommodating itself to its new role, loosening its dogmas, accepting some degree of syncretism with the beliefs and practices of its vastly expanded roll of adherents, reconciling itself to social and institutional hierarchies, and becoming comfortable with coercion.

The other broad theme is that Christianity’s spread and endurance was characterized by a high degree of contingency. As an elite movement, its success was tied to the fortunes of those in power or those who saw Christianity as a means to get at it. Acceptance of belief was not always about personal conviction as opposed to perceived advantage. And political power was by no means stable in the late antique Mediterranean or early medieval Europe, and often those who came out victorious dictated what form of Christianity continued as orthodoxy. Trinitarian and Christological disputes that are traditionally portrayed as being decided by councils and theologians were often very dependent on the outcome of battles or dynastic politics.

Questionable areas of focus

Many of Heather’s arguments are persuasive, but he also over-states his case in some areas. Few need to be convinced that Christianity has not actually existed in a complete, unchanging form for the last two thousand years, or that the Church was not always free of outside influences. Heather also stops his narrative in Christendom somewhat abruptly in the early 13th century. Yet a reader with a Reformed background and a historically conscious perspective can easily transpose his arguments onto the events that would occur three centuries later. The Reformation was certainly a politically contingent event. Had Emperor Charles V not been so distracted by foreign affairs or been unable to risk a clash with the German nobility, Martin Luther would likely have gone the way of Savonarola.

Such a reflection also leads to a further criticism of Heather’s book: a certain arbitrariness in what parts of the Christian story are told. In his discussion of the interplay between Christianity and the late Roman state, there is little mention of the Christian traditions that flourished beyond the Empire’s borders (and many of which have, sadly, since vanished).

As we move forward into the medieval period, the focus narrows on Christianity’s western and Latin form, to the general neglect of the rich Byzantine tradition of Orthodox Christianity. A different relationship between Church and State formed in Eastern Christianity, as did a vibrant and complex religious culture. In reading of how it took centuries for Roman Catholicism to articulate its doctrine and institutions, and for religious practices and beliefs to be absorbed by or forced upon the population, I could not help but think of Lord Acton’s lines about how when “Western Europe lay under the grasp of masters the ablest of whom could not write their names,” the Greek east had preserved “all the monuments of early Christianity” and “even the peasants of Bulgaria knew the New Testament by heart.”

Flaws aside, Christendom is a detailed reminder of how the personal experience of faith is not hermetically sealed off from the cultural, economic and political forces of the world. It is a lesson just as valid today, when it often remains difficult to see just how much our faith and our politics intersect.