God's War: A New History of the Crusades

Such imagery and language as well as the martial history of the biblical Chosen People of the Old Testament fed directly the world-view of the crusaders, providing rich quarries alike for preachers and chroniclers. Although the surviving letters from the First Crusaders contain only one reference to the Apocalypse, commentators were full of it. In a notorious passage, Raymond of Aguilers, chaplain to Raymond IV, count of Toulouse, one of the leaders of the First Crusade, who witnessed the fall of Jerusalem in 1099, described the ensuing massacre on the Temple Mount: ‘it is sufficient to relate that in the Temple of Solomon and the portico crusaders rode in blood to the knees and bridles of their horses’.⁶ Whatever the atrocities performed that day, Raymond was quoting Revelation 14:20: ‘And the winepress was trodden without the city, and blood came out of the winepress, even unto the horse bridles.’ It is hard to exaggerate the dependence of Raymond’s contemporaries on the Scriptures for imagery and language. Many saw Urban II’s holy war as the fulfilment of biblical prophecy or an imitation and renewal of scriptural struggles. Just as the reformed papacy of the eleventh century loudly proclaimed its adherence to the so-called New Testament Petrine texts in which Christ committed His Church to St Peter, so the holy war itself was perceived and possibly designed to revolve around Matthew 16:24: ‘If any man will come after me, let him deny himself, and take up his cross, and follow me.’ This was the text referred to in the deal between the south-east German abbey of Göttweig and Wolfker of Kuffern, who had decided to join the march to Jerusalem in 1096 because ‘he wanted to fulfil the Gospel command, “who wishes to follow me”’.⁷

This process of translating the spiritual conflict described by St Paul into a doctrine of battle and reversing the habit of discounting the interminable wars of the Israelites as literal models for Christian behaviour was not sudden. Until the adoption of Christianity by the Roman state, public war had been rejected by theologians such as Origen of Alexandria in the third century, who insisted that the Old Testament wars should be read as allegories of the spiritual battles of the New Covenant. Thereafter, Christianity had to come to terms with more than biblical exegesis. In devising a tentative theoretical justification for war in the fourth and fifth centuries, the Church Fathers incorporated two distinct traditions of legitimate war, the Helleno-Roman and the Jewish.

The fourth-century bc Greek philosopher Aristotle coined the phrase ‘just war’ to describe the categories of acceptable warfare (Politics I: 8). War provided a natural form of acquisition for the state but should not be an end in itself. It could legitimately be deployed in self-defence, to prevent the state’s enslavement; to obtain an empire to benefit the inhabitants of the conquering state; or to enslave non-Hellenes deserving of slavery. The key was the justice of the ends for which the war was fought. In his Politics (VII: 14) Aristotle insisted that ‘war must be for the sake of peace’. There was no concept of a religious war per se nor of religious disapproval of war, as public religion resembled a civic cult, thus the needs of a virtuous state were almost by definition just. Even while Aristotle deplored the Spartan attitude of war for its own sake, Athenian just war in practice accommodated the tradition of victors’ genocide of those they defeated. To Aristotle’s just ends, Roman Law added just cause, a causa belli as the historian Livy put it, based on contractual relations. From the Latin for peace, pax, derived from the verb pangere, meaning to enter into a contract, it was argued that war was justified if one party was guilty of breaking an agreement or injuring the other. As a legal procedure, to jurists such as Cicero, just war required formal declaration and purposes of defence, recovering lost goods or punishment. The enemy of a just war was ipso facto guilty. Cicero also argued for right conduct, such as virtue or courage, in waging a just war. The practical consequences of these theories lent the aura of justice to all Rome’s wars against external enemies, especially barbarians, identified as hostes, public enemies, automatically legitimate targets of just war.⁸

CHRISTIAN JUST WAR