The Genesis of the Crusades: The Springs of Western Ideas of Holy War


By H.E.j. Cowdrey


Introduction: Our subject in this volume is how men thought about war in the medieval and early modern periods, and how their thinking has contributed to contemporary outlooks upon warfare and violence. A convenient starting point for our deliberations is a comment upon changes in the Western estimate of warfare over the centuries, which William Stubbs made in the third volume of his Constitutional History of England, originally published in 1878. “The kings of the middle ages,” he wrote, “went to war for rights, not for interests, still less for ideas.” For rights . . . for interests . . . for ideas. Implicit in those three phrases is a downhill progression from bad to worse in the pretexts upon which wars have been waged; and Stubbs was not without a remarkably prophetic concern that, with the French Revolution, the Europe he studied and lived in might not have embarked upon its final stage. He made his comment with King Henry V of England in mind. Henry went to war for rights. He had, or at least he professed to have, a rightful claim to the crown of France, which he was denied; his warfare was, therefore, the continuation of a judicial process by other means. If he gloried in war as the highest and noblest work of kings, his aggressive designs were, nevertheless, subject to a measure of legal justification. Such legal justification itself implied principles that, however imperfectly kings themselves may have attended to them, reinforced the doctrines of limited warfare that, at least since the early twelfth century, canonists and schoolmen had been seek­ ing to formulate.

We move on from the fifteenth century to the seventeenth and eighteenth centuries. By then, kings such as Louis XIV and Frederick II fought for interests—like the Spanish Succession, or control of Silesia. That was a rather worse sort of warfare, Stubbs thought, than warfare for rights. No cloak of justice now hid naked selfishness. Kings advanced excuses, rather than legal justifications, for their aggressions. And yet, warfare for interests was still not too bad: it remained limited; few people were killed, and those were mostly soldiers. As regards thought about war, the centuries of warfare for interests consolidated and continued the doctrines of limited war that had gained increasing currency in the Middle Ages.

With the French Revolutionary period, however, there moved toward the center of the picture a far more destructive and fearful warfare—warfare for ideas. Stubbs was not confident that what he saw as having been the formative and stabilizing principles of European history—dynasty, nationalities, and freedom, all of them having deep roots in the Christian tradition—were in his day any longer secure. In particular, the principle of nationalities, in its current form, had been “mostly unlucky in its prophet” (that is, Napoleon I); and Stubbs was also alarmed by “the first attempts at a propaganda of liberty, and the first attempts at a propaganda of nationality” in the French Revolution. He seems to have been anxious lest such unlimited warfare for ideas as had ominously marked the Revolutionary epoch and had been resurgent under Napoleon III, might become the order of the day.

There were grounds for such anxiety, quite apart from those that we, with our experience of the total wars of the present century, can recognize with the benefit of hindsight. For Europe inherited from the Middle Ages another tradition about warfare, besides that of limited war. The eleventh and following centuries had witnessed the vast upsurges of the Crusades, in whose inception Stubbs had rightly seen a “war of idea.” In the name of God the participants sought to extirpate those whom they saw as aliens, both inside and outside Christian society. “Scarcely a single movement now visible in the current of modern affairs,” wrote Stubbs, again, “but can be traced back with some distinctness to its origin in the early middle ages. ” The Crusades were such a point of origin; they were effectively the starting point of a view of total warfare that stands in contrast to limited hostilities for rights or interests. They left an indelible mark upon the Western consciousness, which goes far to justify Stubbs’s half-articulated fear lest warfare for ideas— secularized, now, but waged with quasi-religious fervor—might again become prevalent.

My concern today is with this last kind of warfare—total, ideological warfare, and the springs of its compulsion upon men. I shall try to set out what seem to me to emerge from modern scholarly inquiry as the reasons why, in the late eleventh century, men came, in the Crusade, to wage it so extensively against what seemed alien to them, and why what they then did has shaped Western ideas so profoundly. I shall then try to suggest some lessons that might today be drawn from the rise and decline of crusading ideas, and from the alternative tradition of limited warfare, which is also a medieval legacy.

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