Siege of Alexandria ( 641 ) The major Mediterranean port of Alexandria , the capital of the province of Egypt , was permanently seized from the ( Eastern Roman , or ) Byzantine Empire by forces of the Rashidun Caliphate in the middle of the 7th Century AD . This marked the end of Eastern Roman maritime power over ( and financial dominance of ) the eastern Mediterranean and thus brought about a decisive geopolitical shift . Historical overview . With the death of Muhammad in 632 AD , the Muslim world began a period of rapid expansion . Under the rule of the first caliphs , the Rashidun , Muslim armies began assaulting the borders of both Sassanid Persia and the Byzantine Empire . Neither of the two former powers was prepared for the aggressive expansion of the Arabs , as both largely underestimated Islam and its growing support ; this is best depicted by the ambivalent views held by the Byzantines and the painstakingly slow reaction of the Sassanids . After smashing both the Byzantines at Yarmuk ( 636 ) and the Persians at Qadisiyah ( 637 ) , Muslim expansion set it sights south towards the rich provinces of Byzantine Africa . Following Muslim conquest , the local populace and political infrastructure was left largely intact , albeit under Muslim control . Some groups were persecuted , namely anyone deemed to be " pagan " or an " idolater " . The Library of Alexandria was also destroyed , although blame for its destruction is disputed . The Muslim people were tolerant of the Jews and Christians of captured regions . Many rose to positions of relative power and affluence in the new cities like Baghdad . This led to a stable and smooth running empire . The only major differentiation existent between Muslims and non - Muslims was the system by which they were taxed . Non believers were obligated to pay a higher tax to the local government called the jizya , while Muslims had to pay a Zakāt . Byzantine Alexandria . The rulers of Alexandria before the arrival of Islam were the Byzantines . A heavily trafficked port city , Alexandria was crucial to maintaining imperial control over the region , based on its large Greco - Egyptian population and economic importance . The population of Alexandria was heavily influenced by both the cultural and religious views of their Eastern Roman Empire rulers ; nevertheless , the majority of the population spoke Coptic , rather than Latin or Greek . Thus , the main agents of cultural diffusion at the time of the arrival of Islam were the Coptic Christians . The Byzantines relied on Egypt as the main center of food production for wheat and other foodstuffs . Alexandria also functioned as one of Byzantium ’ s primary army and naval bases , as there was normally a significant imperial garrison stationed in the city . With the loss of Jerusalem in 638 though , much of Byzantine attention was drawn towards strengthening their hold of the frontier , chiefly in Anatolia and Egypt . Even though they would be able to successfully hold Asia Minor and retain it as an imperial base province , as time went on , Egypt became increasingly difficult to defend . Muslim conquest of Egypt . In 634 , the Muslim leader Umar ascended to the role of caliph and inherited a heterogeneous and rapidly expanding Islamic empire . Throughout the early 640s , he set his sights on the economically desirable province of Egypt and its capital city of Alexandria . The Muslim invasion of Egypt was led by the commander Amr ibn Al - Asi , who commanded a force larger than any army the Byzantines could field at the time , resulting from their crushing defeat at Yarmuk four years earlier . The original attempts of the Arab forces were not directed solely towards Alexandria but rather at removing the Byzantine fortress of Babylon on the Nile Delta . The destruction of the Byzantine military power at the ensuing battle of Heliopolis , also known as Ain Shams , in the summer of 640 and the victory over the Byzantine defenders at Babylon effectively broke Byzantine power in Egypt . Fall of Alexandria and aftermath . Following the destruction of the Byzantine forces at Heliopolis , the city of Alexandria was left virtually defenseless and it is likely that only a fraction of provincial forces remained garrisoned in the city itself . Though the Byzantines were unable to field an effective force , Alexandria ' s substantial walls proved to be valuable assets and were adequate in keeping the Muslim attackers at bay . However , on November 8 , 641 , after a fourteen month siege , Byzantine officials at last capitulated to Amr , turning the city over to Muslim hands . The impact of such a major event as the loss of Alexandria to Muslim forces was felt throughout the Mediterranean world . The decrease in the annual grain shipments from Egypt struck a decisive blow to the Byzantine economy ; besides the simple fact of fewer available resources , the empire lost untold thousands in taxes from the grain merchants now traveling southward towards Damascus and Alexandria . In such a weakened condition the empire was barely able to bail itself out financially and in some instances , had to resort to piracy , in some cases attacking merchant ships and “ requisitioning ” their cargo before distributing it to Byzantine or allied ports . Historically , Alexandria had provided Byzantium with a steady income of both money and luxury items , though some scholars speculate that the imposition of especially high taxes in the final decades of Byzantine rule may have been a considerable factor in causing a sizeable amount of the city ’ s population to defect from Byzantine stewardship to side with the Muslim invaders . Byzantine counterattack . There were several Byzantine attempts to retake Alexandria . Though none of these were successful for a sustained period of time , Byzantine forces were able to briefly regain control of the city in 645 . Arab chroniclers tell of a massive fleet and army sent by the Byzantines with the goal of retaking Alexandria . The imperial forces were led by a lower ranking imperial official named Manuel . After entering the city without facing much resistance , the Byzantines were able to regain control of both Alexandria and the surrounding Egyptian countryside . The Muslims retaliated by readying a large force of 15 , 000 who promptly set out to retake the city under command of the veteran Amr ibn Al - Asi . The Byzantines , following their standard tactical doctrine , advanced out of the city and sought an open battle away from the shelter of their fortifications . Accounts of the battle portray the Muslim forces as relying heavily on their archers before eventually assaulting the Byzantine positions , driving many back and routing the rest in the process . After this , the Byzantines were utterly defeated and withdrew from the region . In 654 , yet another attempt to bring Alexandria back into imperial hands failed when an invasion force sent by Constans II was repulsed . This generally marks the end of Byzantine attempts to retake the city . Life under Islamic rule . Once subdued , the native population of Alexandria was remarkably receptive toward the rule of their Islamic governors . In regards to the treatment of the native population , many sources point out visible persecution towards the native Coptic Christian population in Alexandria , a " religious tax " was imposed on any Dhimmis ( un - converted ) Egyptian . The protection of the Dhimmis ( unconverted ) was guaranteed in return for a payment of Jizyah ( poll tax ) of supposedly fixed taxes , which were embodied in the terms of the capitulation , at two dinars per adult male , and an additional kharaj ( land tax ) payable by those ( including churches ) possessing land in the provinces . In addition , the protected population was required to provide a measure of clothing and hospitality to any itinerant Muslim . This description is vague enough to cover the innumerable variations of interpretation offered by Arab chroniclers , jurists , and writers on taxation , to say nothing of many of their modern successors concerning the imposition of these taxes . Much of this confused material reflects the theoretical variations of a later date . Nevertheless , contemporary papyri as well as some historical sources show clearly that the Dhimmis in early Muslim Egypt were , in fact , the victims not so much of a system fixed ab origine by the capitulation but of frequent and seemingly haphazard changes in status and in levels and incidence of taxation . ” In a later section LeBon further explains , “ The lack of mercy and tolerance of the conquerors were among the reasons for the spread of their conquests and for the nations ’ The imposition of their faith and regulations and language , which became deeply rooted . Egypt is the most evident proof of this . It adopted what the Arabs had brought over , and reserved it . Thus the majority of the population of Alexandria where ready to resist Amr , although the Copts wanted peace , but where denied this by Amr . ” ' Amr kept his way until he arrived in Alexandria whose inhabitants he found ready to resist him , but the Copts in it preferred peace . Al - Mukaukis communicated with ' Amr and asked him for peace and a truce for a time ; but ' Amr refused . Al - Mukaukis then ordered that the women stand on the wall with their faces turned towards the city , and that the men stand armed , with their faces towards the Moslems , thus hoping to scare them . ' Amr sent word , saying , " We see what you have done . It was not by mere numbers that we conquered those we have conquered . We have met your king Heraclius , and there befell him what has befallen him . " Hearing this , al - Mukaukis said to his followers , " These people are telling the truth . They have chased our king from his kingdom as far as Constantinople . It is much more preferable , therefore , that we submit . " His followers , however , spoke harshly to him and insisted on fighting . The Moslems fought fiercely against them and invested them for three months . At last , ' Amr reduced the city by the sword and plundered all that was in it , sparing its inhabitants of whom none was killed or taken captive . He reduced them to the position of dhimmis like the people of Alyunah . He communicated the news of the victory to ' Umar through Mu ' awiyah ibn - Hudaij al - Kindi ( later as - Sakuni ) and sent with him the fifth . “ And when [ Amr ] saw the patriarch , he received him with respect , and said to his companions and private friends : ‘ Verily in all the lands of which we have taken possession hitherto I have never seen a man of God like this man . Then Amr turned to him , and said to him : ‘ Resume the government of all your churches and of your people , and administer their affairs . And if you will pray for me , that I may go to the West and to Pentapolis , and take possession of them , as I have of Egypt , and return to you in safety and speedily , I will do for you all that you shall ask of me . ” Then the holy patriarch Benjamin prayed for Amr , and pronounced an eloquent discourse , which made Amr and those present with him marvel , and which contained words of exhortation and much profit for those that heard him ; and he revealed certain matters to Amr , and departed from his presence honored and revered . ” Islamic influence . Culturally , the city continued to function much the way it had under Byzantine rule . Greek , Coptic , and Arabic were all spoken fluently throughout the city and documents continued to be published Greek and Coptic for some time following the takeover . Coptic was also continued in the fields of medicine , mathematics , and alchemy , whose practices thrived under the budding advances of Islamic intellectualism . After the 11th century however , Arabic replaced Greek and Coptic as the principal language of the city . In terms of religion , Alexandria was largely characterized by its heterogeneous makeup both before and after the advent of Islam . Indeed from the third century on , Alexandria served as a major base for both the practice of Monophysitism and Nestorianism , as well as a surprising number of other Christian sects that found refuge in Egypt . It is also interesting to note that from a cultural perspective the practice of marriage between Muslim men and non - Muslim women was a fairly common one , and at least a sizeable portion of the Muslim invasion force that settled in and around the city of Alexandria took native Greek and Berber women as their brides . As this was typically discouraged by the umma and prohibited by the reigning caliph Umar , this gives credence to the Islamic state ' s desire to respect the lives of the local population rather than act as agents of disorder . The fall of Alexandria and the acquisition of the Byzantine Empire ' s oriental provinces of Egypt and Syria are generally seen as a critical step towards the culmination of uniquely Islamic identity . The importance of Alexandria as the staging point for future conquests and economic purposes should not be dismissed . It is accurate then to say that the loss of these provinces paved the way for the future Muslim conquest of the Byzantine Exarchate of Africa , which included key cities such as Cyrenaica ( 642 ) , Tripoli ( 643 ) , and Kairouan ( 670 ) . Thus the fall of Alexandria accentuated a clearly defined geopolitical shift in influence from the regions of interior Arabia to those of the Mediterranean and in the ensuing centuries , the significance of these conquests would allow Egypt to become the seat of dominant Muslim law .