Yet others were richer still. Across the desert from Syria, where the humiliating collapse of the House of Sasan into debilitation and factionalism had brought a beardless king by the name of Yazdegird to the throne, Iranshahr itself was no less exhausted and divided than its royal family. The marks of the Roman invasion still scarred the landscape. The River Tigris, having burst its banks in AD 629, had swept away an immense swath of irrigation works and left Kavad’s great canal silted up. Parthian warlords, snarling and snapping as ever, now threatened the entire fabric of the imperial high command with disintegration. Never—not even in the dark days following the death of Peroz—had the empire been so enfeebled; and the Arabs, alert as they were to the scents of weakness, well knew it. Either a few weeks or a few years after the Roman defeat at the Yarmuk—the sources, as usual, are at sixes and sevens—a similarly decisive battle was fought on Iranshahr’s desert flank.116 Qadisiyya was a small, palm-fringed town just to the south of the one-time Lakhmid capital of Hira. Now, it would be the scene of an epically terminal disaster for Iranshahr. After fighting that spanned several days, and the failure of elephants as well as the Persian heavy cavalry to turn the tide, the Arabs emerged triumphant. Their women, stalking the palm groves, were said to have busied themselves slitting the throats of those of the enemy still left there alive. Meanwhile, the exultant Arab army, pursuing the remnants of their defeated foes across canals and pontoon bridges, caught up with the fugitives amid the ruins of Babylon and briskly wiped them out. Iranshahr had been decapitated, “for all the leading nobles were killed.”117 Ctesiphon, a bare hundred miles to the north, now lay directly in the Arabs’ path. Its fall, with the flower of the empire’s chivalry left blackened and rotting in the killing fields of the south, was only a matter of time. Sure enough, despite bitter resistance that seems to have lasted almost a year, the great city was duly stormed. Yazdegird himself, amid much confusion, managed to escape his doomed capital, zigzagging across the mudflats in a desperate effort to evade his pursuers. He finally reached the relative security of the Iranian uplands and his ancestral hometown of Istakhr, from which Ardashir, five centuries previously, had embarked on his own great project of conquest; but the royal regalia and the imperial treasury, all were lost. So too was Mesopotamia—which the invaders, in imitation of the Persians, knew by the name of “Iraq.”
That Arab fingers could prod at the crown worn by Khusrow the Great; that Arab feet could tread on carpets from the royal palace woven with gold and adorned with precious stones; that Arab prayers could be heard in the great throne room of Ctesiphon, from the sides of which statues of Yazdegird’s ancestors gazed out stern and impassive, oblivious to the ruin that had engulfed the House of Sasan: all this, in the opinion of the Arabs themselves, taught a lesson so edifying that they would never tire of repeating it. The coin of contempt dealt them for so long by Caesar and Shahanshah alike had been richly, deliciously, repaid. Two and a half centuries on from Qadisiyya, by which time the Muslims ruled an empire even vaster than Khusrow the Great’s, their pride in having scorned superpower dazzle could still rank for them as the surest measure of their dignity. “In the past, those of us who came to you were obedient to you, they humbled themselves before you, they sought what was in your hands.” So one Arab, as pious as he was lacking in personal hygiene, was supposed to have told the silken Persians on the eve of the great battle. “But now we no longer come to you looking for the things of this world. Our desire and aspiration is for paradise.”118
Hairy, badly dressed, and stinking of camel as he was, this ambassador to the perfumed tents of the Persian high command would be commemorated in histories of the conquest as the heroic embodiment of Muslim brotherhood. “God loves not the swaggering and the conceited.”119 So the Prophet had taught. Even though, if tradition is to be trusted, Muhammad died in 632, two whole years before the first rubbing of a superpower nose in the dirt, it was his revelations, of a God who humbles the proud, and slaughters them in battle, and permits them to be despoiled of all their goods, that had given the Arabs the courage and sheer self-confidence to go eyeball to eyeball with their former masters.120 Riding in to meet Roman or Persian officials, their ambassadors were said to have made a point of trampling down their cushions and stabbing with spears at their carpets. The conquest of the world, and the scorning of its seductions: such, it seemed to Muslim historians writing centuries later, had been the supreme achievement of the generation that had known Muhammad.
It had one supreme exemplar. Umar bin al-Khattab had ranked as the most formidable and domineering of all the Prophet’s companions, the leader under whose guidance both Syria and Iraq had been won, the veritable sword arm of the Prophet. Tradition would commemorate him not merely as a great Amir—“commander”—but as something very much more: as a Muslim so flame-lit by his knowledge of God’s will that several Qur’anic verses were said to have been revealed purely to provide his opinions with some heavenly back-up. Even Muhammad, according to certain traditions, had acknowledged that Umar was the better Muslim of the two. “When people differ on any issue,” one celebrated ruling declared, “look for Umar’s doing and abide by it.”121 Like the Qur’an itself, then, the character of the second Caliph was a book in which might be read the lessons of God’s will. Mighty warrior and mighty ascetic; quick to draw his sword and no less quick to trample down in righteous scorn the luxuries won by that same sword; a man who from his mud-brick home in Medina could direct the overthrow of mighty empires, and yet who, if he saw his lieutenants dressed in silks and brocade, would leap down from his saddle and pelt them with stones: such, in the opinion of Muslim scholars, was the man who had secured the world for Islam.
A plausible characterisation? Certainly, as with Muhammad, so with Umar—his historicity is beyond dispute. An Armenian bishop, writing a decade or so after Qadisiyya, described Umar in a brief, throwaway sentence much as Muslim historians would subsequently do: as a mighty potentate coordinating the advance of “the sons of Ishmael” from the depths of the desert.122 Nor is that all. There do indeed seem to be found, preserved in the traditions that Muslims would record of the Sahabah, the “Companions,” of Muhammad, authentic echoes of the God-haunted and strife-torn age that had witnessed the Futuh—the “Conquest.” If there seems no reason to doubt that Umar, that model of ferocious piety, was directly inspired by the awesome thunder of the Prophet’s revelations, then so too is it evident that the Prophet himself, in his summoning of the Arabs to holy war, was perfectly in accord with the spirit of the times. “In truth,” he informed his followers, “the punishment of those who make war against God and His Messenger, and roam the earth corrupting it, is that they be killed, or crucified, or have their hands and feet amputated, alternately, or be exiled from the land.”123 Such a message was all the more resonant, no doubt, for being delivered direct from the Almighty Himself; and yet, the sentiments informing it would have been instantly recognisable to anyone familiar with the workings of Roman power. Whether it was Justinian breaking the rebellious Samaritans, or Saint Simeon incinerating Mundhir with a fireball, or Heraclius bringing ruin to the fire-temples of the Persians, examples were hardly lacking of spectacular violence committed in the cause of God. Umar, turning the pretensions of the Christian empire back upon itself, seemed to those he conquered, as well as to those he commanded, a warlord of a thoroughly recognisable kind. What added incomparably to his prestige, however, and did truly suggest something novel, was that his earth-shaking qualities as a generalissimo were combined with a most distinctive cast of virtue. Rather than ape the manners of a Caesar, as the Ghassanid kings had done, he drew on the example of a quite different kind of Christian. Umar’s threadbare robes, his diet of bread, salt and water, and his rejection of worldly riches would have reminded anyone from the desert reaches beyond Palestine of a very particular kind of person. Monks out in the Judaean desert had long been casting themselves as warriors of God. The achievement of Umar was to take such language to a literal, and previously unimagined, extreme.