All Arabs who could bear arms were soldiers of Islam and, at the call of the Caliph, armies sprang into being. The Caliph appointed leaders who commanded their troops, led them in prayers, acted as judges and were in all respects the minor replicas of their founder.
The Arab armies were mostly composed of cavalry and therefore had great mobility, resulting in their outstanding victories in such a short period of time (it was through these campaigns that the stock of the Arab horse spread all over the world). Military strategy developed gradually. Strict rules on the Arab commanders were relaxed when the caliphs realised that in order to maintain Arab authority the Arabs needed to conform to their captors in certain standards of apparel and living.
During the early years of the caliphate three large areas were won for Islam by force of arms. Firstly, Arabia then Syria as the decisive battles of Qadisiyyah, 737 and Nehavend 641 made an end of the Persian Empire. When Umar took Syria he appointed Qadis and in doing so set a pattern of separating the judiciary from the military in the provinces. Finally, under Uthman (644-656) Islam extended westward along the North African coast.
There appears to be a mixture of force, persuasion, Arab nationalism and the desire for booty attached to the early Islamic mission. The last ‘revealed’ sura promoted warfare and along with many other war-like verses from the Quran led to the earliest abandonment of peaceful measures in propagating Islam. This seems to be the stand taken by the first Khalif, Abu Bakr, who said “When a people leaveth off to fight in the ways of the Lord, the Lord also casteth off that people.”
It does not seem that religious zeal was a major factor in the consciousness of the Arab protagonists. The Arab apologist Al-Kindi observed that hunger and want, and the desire for what their more prosperous neighbours had, seems to have been the drawing power as the inhospitable deserts were compared with the richer lands. The movement was based on the Islamic theocracy but its success lay in the prevailing conditions of the conquered people. Yet, the material inducements to fight for Islam, great as they were, seemed by some ardent missionaries to have been of small estimation in comparison with the glories and delights of Paradise.
The Conquests of Arabia
The outlying Arabs, the Christian Bedouins, like Banu Ghassan, who lay between the lands to be conquered and the conquerors abandoned Christianity in favour of the Arab nationalism movement. Some tribes remained Christian like Banu Taghlib; the fact that they and others remained Christian up to the time of the Abbasid caliphs shows that all were not destroyed by force. The tribe of Banu Ghassan, pure Arabs, who later embraced Christianity in the fourth century still retain their Roman Catholic faith.
United for the first time in their history by the bonds of a common religious enthusiasm, and fired with the prospect of plunder the Arabs burst out of their desert lands. The tribes of Hira rejected all the inducements of Khalid to become Muslims. When the city was being besieged Khalid questioned whether they were Arabs because they would not submit to Islam. The Romans, who had only shortly earlier been victorious over their ancient enemies, the Persians, could not stand against this new foe.
Christian tribes belonging to both side of the Euphrates embraced Islam, similarly most of the Bedouin tribes joined Muhammad after the conquest of northern Syria. Other tribes of Mesopotamia like Banu Namir and Banu Quda’ah became Muslims while some tribes had a mixture of Muslim, Christian and pagan members
The Syrian Campaign
Most of the Syrian Arabs threw in their lot with their fellow-countrymen of Arabia. Some of them, even those who remained Christians, did not scruple to fight on the side of their compatriots, and in the subsequent campaign in Persia we hear of a Christian chief of the Bani Tay upholding the Arab cause in 643 A.D. Tribes like the Bani Namr made a large contribution; but it was plunder and not the propagation of Islam that attracted them to these campaigns.
In 635 Khalid, with his united Arab forces besieged Damascus for six months. Those in Damascus made terms with the Arabs: they secured for themselves immunity from plunder and other favourable conditions, other cities quickly followed and became tributaries to the Arabs. Once the initial fear of invading armies had been overcome they preferred to stick with Muslim conditions rather than those of the Roman Empire.
Rome’s sense of being a united nation had declined after the times of Justinian and religious passions were the only uniting frame. When religious controversy between the orthodox and the Monophsites, (who flourished in Egypt and Syria particularly), ignited the controversy blazed up even more as each party accused the other of heresy. Islam however, appeared with the promise of religious tolerance. The provinces on account of their Nestorian (Monophysite) beliefs experienced a toleration unknown for centuries. In return for paying the jaziyah tax they were assured of protection of life, property and religious belief. Michael the Elder, writing in the latter half of the 12th century viewed the Islamic conquest as providential as it gave a period of peace.
For the most part the non-Arab population of Christians in the great cities of the eastern province of Byzantium remained faithful to the Christian faith.
In 638 the Romans were defeated at the Battle of Yarmouk by Khalid which meant that the Muslims now had Palestine open before them. The Muslim armies under the commandership of Amr ibn Al-As reached Jerusalem and lay siege of the city. Amr was later joined by prominent Muslim commanders such as Khalid and Abu Ubaidah. The conquest was attended with difficulty until the arrival of Khalif ‘Umar with four thousand horses. Seeing little hope in resisting, the Christians in Jerusalem sent a deputation to the city walls with a flag of truce, asking for a parley.
There appears to be conflicting views as to what actual conditions were placed in the treaty. Muslims emphasise the benevolence of ‘Umar by saying that the settlement of Jerusalem secured security for lives, possessions, churches and their crosses and other religious concerns. They tell us that tribute was imposed but the richer were charged higher than the poor. They tell us that when ’Umar visited the Church of the Resurrection at the time of the Muslim prayer rather than praying he departed lest his followers claimed the church as a place of Muslim worship. It is said that Umar allowed a sum of money to be given to the Christian lepers out of public funds and that in his last testament he requested that the dhimmis be given continued protection and were not to be harassed.
However, Jalaluddin as-Suyuti (d. AH 911) writes in his History of the Temple of Jerusalem the terms of the treaty accepted by Jerusalem’s Patriarch Sophronius: they requested that their chapels, churches, or monasteries were not to be polluted; they would not prevent Muslims from entering them by day or night; they were to receive the Muslim traveller and give him food and lodgings for three nights; they would not harbour any spy or any enemy of Islam in their churches; they will not teach their children the Quran; they will not make a show of their Christianity nor invite any to embrace it; they will not prevent any of their kinsmen from embracing Islam, if they so wish; they will honour the Muslim and stand up in assemblies when they take their seats; they will not imitate the Muslim in dress, either the cap, turban, sandals or the parting of the hair nor will they write in their language or adopt their surnames; they will not ride on great saddles nor carry or suspend their swords on their belts; they will not engrave Arabic inscriptions on their rings; they will not sell wine; they will not display the cross on their churches, sacred books or in the streets or market places of Muslims; they will strike the bells lightly and not recite their services in a loud voice when Muslims are present. When ‘Umar ratified the treaty he added “we will not strike any Muslim.” The 12,000 Greeks who lived alongside the 50,000 native inhabitants were required to leave the city within three days. These were the terms of the capitulation.
Islam was first introduced by the Arabs who invaded Egypt under ‘Amr b. al-‘As in 640 and three years later the Byzantine troops abandoned the vast Christian population. Their success was greatly due to the Christians who welcomed the conquerors. The Byzantines were hated for their oppressive administration but chiefly because of theological rancour. The majority Jacobites (Copts) had been treated roughly by the Orthodox adherents of the court. Some were tortured then thrown into the sea, many followed their patriarch into exile to escape the hands of the persecutors while many more made a pretence of accepting Chalcedon theology. On payment of tribute ‘Amr left them in undisturbed possession of their churches and guaranteed them autonomy in all ecclesiastical matters, delivering them from the interference they had previously experienced. In these early days of Islam there was no evidence of apostasy or undue pressure to convert. The enormous reduction of revenue from capitation tax between the reign of Uthman (643-655) and Umar 2 (717-720) was owed to the enormous amount of conversions. When Hafs .b Walid, who was governor of Egypt in 744 promised that all who became Muslims would be exempt from paying the Jiziyah as many as 24,000 Christians were said to have accepted Islam. A similar proclamation was made by al-Saffah, the first of the Abbasid caliphs soon after his succession in 750. Christians seem to abandon Christianity as lightly as they embraced it. By the seventh century Christianity had little hold on the people of Egypt. It was not that Islam made definite efforts to attract but rather Christianity had an inability to retain. The theological wrangles that caused the Jacobites to be considered a sect were too abstruse for many in opposition to the simple belief in the unity of God
Persecution, did have its part to play in the large reduction of the Jacobite Church, the vast difference between their condition and that of the Christians of Syria, Palestine and Spain of the same period has been explained by the turbulent character of the Copts themselves. Their long struggle with the Byzantines had developed a strong nationalism causing them to drive out the Arabs from Alexandria in 646 and open the gates to the Byzantine troops who however, treated the Copts like enemies. It was the first of many insurrections against Islam due frequently to excessive taxation demands. Copts were not to be always thought of as being the object of persecution for many Copts filled the post of secretaries and scribes in government offices and some amassed considerable wealth. The annals of their ecclesiastical history show clerics held in high honour by princes in the times of tranquillity. It is said that Muslims consider the Copts to be more inclined to Islam than any other Christian group. Vast numbers are said to have converted over the generations and even in the 19th century Copts were voluntarily going over to Islam.
There is perhaps no more tragic event in the history of the church than the fall of the great African church of Tertullian, Cyprian and Augustine which had emerged victorious out of so many persecutions. Most of the Christians in North Africa were not native to the country as they were either expatriates from Italy or Greece or were the children of expatriates. As the Muslim advance rolled onward the Christians left North Africa and returned to Southern Europe. The Christian population was therefore quite small and suggests that the Arabs did not find a flourishing Christian church in their north Africa conquests.
The Christian church lost its way in North Africa because it was not a united church and it was not a witnessing church. The native population were the Berbers and mission work amongst them was virtually non-existent. Scriptures were not translated, nor did Christian leaders learn their language, therefore, there was no sense of loyalty to the Christian religion. When the conquerors came the Berbers just as easily put on the Muslim coat as they had formerly put on the Christian garb.
There is a lack of evidence as to what happened to the Christian community they are often portrayed as loosing out through fanatical persecution and forced conversion but the evidence is lacking. Massacres, devastation through protracted warfare, there certainly was for example the Christian monks of Egypt were compelled in 722 to pay tribute and be branded like cattle. If caught in attempting to evade this they were scourged or beheaded. Later, especially under the insane tyrant Hakim (996) churches were plundered or destroyed, and a decree of expatriation was contemplated, against the Christians until it was finally relaxed again. At other times cordial relationship with their conquerors gave place to far different feelings as when a number of restrictions were placed on Christians; they must not try to gain a Muslim to the Christian faith; they were forbidden to marry Muslim women; they may not speak unfavourably about Muhammad or the Quran; they were not allowed to display crosses, mourn their dead or sound their church bells in such a way that Muslims would have to hear them; they could not build their houses higher than the Muslims; own thorough-bread horses, or dink wine in public, and they must not allow pigs to be seen. In many places, like the Jews, they had to wear distinctive clothes.
The words of the Muslim general Akba still remind us that Islam progressed with both through military and peaceful measures: “Within thirty years the victorious Muslims had reached the Atlantic Ocean, and their general, Akba, spurring his horse into the sea exclaimed: ‘Great God, if my course were not stopped by the sea, I would still go on to the unknown kingdoms of the West, preaching the unity of Thy Holy Name, and putting to the sword the rebellious nations which refuse to call upon thee’” (Gibbon).
The continent of Africa
The Arabs entered Africa from three different sides. These three streams of immigration were 1) from Egypt, westward as far as Lake Chad; 2) from the north-west southwards as far as Lake Chad and the Niger; 3) from Zanzibar, westwards as far as the Great Lakes (Tanzania and Kenya)
It was in this way that the African Muslims from the north and east joined hands somewhere about the region of Lake Chad converting the whole of Africa north of 10 degree latitude to Islam (The 10/40 Window). This took many hundreds of years to accomplish. Though this in itself is a great wonder we marvel that Islam did not push rapidly further into the south down to the Great Lakes as there was no great powerful Empire present to withstand them.
There have been various methods for the Islamisation of Africa generally, most of the the work of conversion was done by other means than by persuasion, the latter being reserved chiefly for the propagation of sectarian views amongst Muslims themselves.