Omar ibn al-Khattab (died 644) was the second caliph of the Moslems and directed the spectacular Arab conquests and organized the Arab Empire.
Because Omar was one of the most adamant opponents of Mohammed's preaching in Mecca, his dramatically sudden conversion to Islam in 615 is often regarded as a turning point in the career of the Prophet. The fierce loyalty which he gave to Mohammed, both as a warrior in the battles against the Meccans and as an adviser, was reinforced by marriage when his daughter Hafsa married the Prophet.
Nevertheless, in spite of his vigorous support of the Prophet, Omar does not figure prominently in Islamic history until the death of Mohammed in 632, and even then it is as a supporter of Abu Bakr, the first caliph, whose selection Omar imposed on the divided Moslem community by the sheer force of his own personality. Although some modern historians have claimed that Omar was the real power behind the throne during Abu Bakr's short reign (632-634), Omar was careful—if this theory is sound—to stay in the background, perhaps realizing that more vigorous leadership might be resented by the Arab Moslems so soon after the death of their beloved Prophet.
At any rate, upon Abu Bakr's death in 634, Omar assumed the caliphate in his own right, apparently without opposition. The immediate task confronting him was to direct the two-pronged military campaign (which had been launched in 633 by Abu Bakr) against the Byzantines in Palestine and Syria and the Sassanians in Iraq. In both fields of battle Omar gave new energy to his armies by sending new levies of tribal troops. Thus reinforced, the Syrian army, led by the famous general Khalid ibn al-Walid, captured Damascus in 635 and, in the following year, smashed the Byzantine army in Syria at the battle of Yarmuk. Further successful campaigns in Syria led to the conquest of Jerusalem in 638. Because Jerusalem was the third holiest city in Islam, after Mecca and Medina, Omar himself visited it as conqueror. Typically, however, he insisted on presenting himself as a simple desert warrior rather than a mighty potentate.
Simultaneously with the conquest of Syria and Palestine, another of Omar's armies was driving the Persian army from Iraq. Here the decisive battle was fought in 636 at Qadisiya, where a Moslem victory left the Sassanian capital of Ctesiphon virtually defenseless and open to plunder by the Arabs. Once the conquest of Syria had been achieved, the Syrian army was free to attack upper Mesopotamia from the west, and it came under the control of the caliphate in 640.
The conquest of such a vast area in such a relatively short time soon created formidable administrative problems for Omar. Since the Arabs had no experience as rulers of an empire, they were forced to rely to a great extent on the bureaucracies created by the Byzantine and Sassanian governments. Nevertheless, Omar is credited with introducing several new administrative practices and institutions which, in conjunction with the customary practice of the conquered lands, gave stability to the Arab occupation and allowed the conquests to maintain their momentum.
Tradition would have it that Omar announced his innovations in a speech made to the Arab military leaders during a lull in the fighting between the battle of Yarmuk and the occupation of Jerusalem. Though this tradition may well be a reconstruction of the gradual evolution of early Moslem policy, it is probable that Omar did lay down guidelines, at least for the solution of pressing problems. Almost all these were related to finances: how to pay the troops and support the Moslem community on a long-term basis without disrupting the economy of the conquered lands.
In general, Omar's solution was to leave the conquered peoples in possession of their lands and their own religion in exchange for the payment of tribute which was to be disbursed in turn by the Moslem government to its armies and citizens. To institutionalize this policy, a divan, or register, was drawn up which regularized the stipends which Moslems were to be paid according to religious and tribal principles. Relations between Moslems and non-Moslems were further stabilized by exempting the latter from military service and guaranteeing them protection in return for the taxes which they paid.
Undoubtedly of equal importance to these measures was Omar's decision to establish garrison cities, first in Iraq, and later in Egypt, to administer the newly conquered territory and to serve as bases for the invasion of Persia. In this way, Basra and Kufa were founded by Omar in 635, both of which were to become important centers of Islamic civilization. From these cities Omar launched an invasion of Persia in 640 which was climaxed by the defeat of the Sassanian army at the battle of Nihawand in 642; the resultant collapse of Sassanian power opened Persia to relatively easy conquest.
At the same time as Omar's armies were achieving victory in Persia, still another army was invading Egypt. Between 639 and 642 the Arabs succeeded in driving the Byzantines from Egypt and establishing a Moslem government there. Again Omar's policy of establishing new garrison cities was followed with the founding of al-Fustât, later to become Cairo.
With astonishing speed, Omar succeeded in spreading Arab Moslem rule from Persia to Egypt under his political and religious leadership. He was also able to establish a remarkable degree of unity in the empire through the appointment of provincial officials loyal to him and his principles and by setting a stern example of piety and morality at the capital. He is celebrated in Arabic historiography for his unaffected, rough manner, coupled with devotion to his religion—the prototype of the unspoiled Arab ruler. A Persian slave, outraged by Omar's refusal to reduce a heavy tax, mortally wounded the Caliph in 644 while Omar was leading the prayers. Refusing to name his successor on his deathbed, he established still another precedent by appointing a council to choose the new caliph.
The only biography in English is Muhammad Shibli Numani, Omar the Great (Lahore; trans., vol. 1, 1939; rev. ed. 1943; vol. 2, 1957). Detailed studies can be found in William Muir's dated but still useful study The Caliphate (1891; rev. ed. by T. W. Weir, 1915), and in Maulana Muhammad Ali, Early Caliphate (Lahore; trans. 1932). For general background see Thomas W. Arnold, The Caliphate (1924); S. Khuda Bukhsh, The Caliphate (1927); Philip K. Hitti, History of the Arabs (1937; 10th ed. rev. 1970); Carl Brockelmann, History of the Islamic Peoples (1939; trans. 1949); and Bernard Lewis, The Arabs in History (1950; rev. ed. 1958). □