During the almost nine centuries from the advent of Islam in the early seventh century until the conquest of Constantinople in 1453, a considerable Muslim presence came into being in the city as a result of the political, military, religious, economic and socio-cultural relations between Muslims and the Byzantines. Throughout this entire period, the envoys, merchants, travelers, bondsmen and servants who came to the city for a variety of reasons contributed significantly to the Muslim presence in Constantinople.

Many envoys travelled to Constantinople with the purpose of carrying out talks with the Byzantine state before and after military confrontations, negotiating ransom and exchange of prisoners, and cooperating with Byzantium on certain issues. It is reported that the first caliph Abu Bakr sent an envoy to Constantinople to invite Emperor Heraclius to Islam. Umayyad Caliph Walid ibn ‘Abd al-Malik obtained funds, laborers and mosaics for construction works by sending an envoy to Emperor Justinian II. It is also recorded that another Umayyad Caliph ‘Umar Ibn ‘Abd al-‘Aziz sent a letter with an embassy to Emperor Leo III to invite him to Islam, debates were held between the members of the embassy and the emperor on certain foundational religious issues, and the emperor sent a response to the caliph’s letter.

‘Umara Ibn Hamza, who was sent as an envoy to Constantinople by the Abbasid caliph Abu Ja‘far al-Mansur (754-775) was taken to the presence of the emperor only after overcoming three sets of obstacles that included lions, swords and smoke, and he was informed that this a procedure to inflict fear in the hearts of the foreign envoys visiting the Byzantine palace. When Nasr Ibn al-Azhar, sent to Constantinople as the envoy of the Abbasid caliph al-Mutawakkil I, reached the Byzantine palace in official garb wearing a turban, a sword and dagger, and was denied entry into the palace dressed in this manner he returned back. Only on the way back he was convinced to return, and was received by the emperor.

Yahya Ibn Hakam al-Ghazal, sent on a diplomatic mission to the Byzantine Palace, presumably to Emperor Theophilos, by the Andalusian Umayyad ruler ‘Abd al-Rahman II (822-852), built a close relationship with the emperor due to his personality, conduct and diplomatic ingenuity.

The delegation of envoys sent after 949 from Andalusia by ‘Abd al-Rahman III, the Caliph of Cordoba, was welcomed with a grand ceremony by Emperor Constantine VII. They returned to Cordoba after remaining in Constantinople for two years.

When Qadi Abu Bakr al-Baqillani (d.1013), the renowned Ashari theologian and Maliki jurisprudent, was sent as head of a delegation to Constantinople by the Buwayhid ruler ‘Adud al-Dawla (978-983) to discuss the exchange of prisoners and other issues, he was told to remove his shoes and turban on entering the palace. When he refused and wanted to leave the emperor was informed, and the envoy was granted permission to enter the palace in this manner. Only then the negotiations took place. It is reported that as al-Baqillani approached the emperor, he came across a door that was so low that one had to bow to walk through. He avoided bowing before the emperor by turning around and passing through the door backwards. At the banquet given in honor of the delegation, when al-Baqillani expressed his concern about whether the food served contained dishes such as pork, questionable from a Muslim point of view, he was ensured that none of the food served was prohibited for Muslims. al-Baqillani held civilized, fruitful discussions with religious dignitaries, including Patriarch Nicholas II, thus earning the admiration of the Byzantines. He was honored by being invited to the emperor’s banquet, after which he returned to his country.

It is reported that after the third siege of Constantinople, by Maslama ibn ‘Abd al-Malik during the reign of the Umayyad ruler Sulayman ibn ‘Abd al-Malik (715-717), a mosque was constructed in Constantinople by Maslama. Several Islamic sources mention this building, and in De Administrando Imperio, a work attributed to the Emperor Constantine Porphyrogenitus III, it is clearly stated that a mosque was constructed in Constantinople on the request of Maslama. In the treaties made between the Abbasids, Fatimids, Ayyubids and the Byzantine Empire, we see that this mosque that was built on the request of Maslama gained recognition, particularly in connection with the question of in whose name the sermons were to be delivered. During the reign of the Fatimid Caliph al-Hakim (996-1021), the sermons at this mosque in Constantinople were delivered in his name. In accordance with the treaty made during the period of al-Zahir al-Fatimi (1021-1036), the emperor ordered the restoration of the mosque, assigned a muazzin, and in 1027 the sermon was delivered in the name of al-Zahir. As a sign of his gratitude, the Byzantine emperor, Constantine IX Monomakos (1042-1055) sent various gifts to Tughrul Bey upon his release of the Abkhazian ruler without ransom, and also ordered the restoration of the mosque, granted permission for holding prayers in it, and in 1049 the sermon was delivered in the names of Tughrul Bey and the Abbasid caliph. In 1055, the Fatimid caliph al-Mustansir sent an envoy to Constantinople, where he met the envoy of Sultan Tughrul Bey. In the letter delivered by Tughrul Bey’s envoy, it was requested that the Byzantine administration grant his envoy permission to hold prayers in the mosque. Permission was granted, and the Friday sermon was delivered in the name of the Abbasid caliph, al-Qa’im bi-Amr Allah. In 1188, the Byzantine emperor, Isaakios II, sent an envoy to Salah al-Din al-Ayyubi, proposing that the sermon in this mosque would we read in the name of the Sultan and Abbasid caliph in return for the old Orthodox churches in Jerusalem being placed under the order of the Byzantine Empire. Salah al-Din al-Ayyubi welcomed the emperor’s proposal. Along with the emperor’s envoy he sent an envoy, a pulpit, a preacher, a muazzin and memorizers (huffaz) of the Quran for the mosque. This delegation, which reached Constantinople by sea, was welcomed in the city in a ceremony attended by the emperor, the Muslim community and Muslim merchants. The sermon, following the Friday prayers, was delivered in the name of the Abbasid caliph and the sultan.

1- The tomb of Abu Ayyub al-Ansari, the companion of the Prophet Muhammad

During the reign of Alexsios Angelos III (1195-1203), this mosque was destroyed in a riot, and was consequently rebuilt. It was destroyed once again during the Fourth Crusade in 1204, and despite the resistance of Muslims in the mosque and the Greeks who helped them, it was looted and burned down. Emperor Michael VIII Palaiologos ordered the reconstruction of the mosque, and the Mamluk ruler Baybars sent mats, gold candleholders, curtains, carpets and other objects as gifts to the mosque. There are claims that this mosque was later transformed into a church.

Semavi Eyice claims that this mosque is not the Arab Mosque, the largest mosque transformed from a church into a mosque in Galata, Istanbul. In compliance with the tradition of transforming the largest church in conquered cities into mosques, after the conquest this church was transformed into a mosque in 1475 by Sultan Mehmed II. After the fall of the Nasrids in Granada, Spain, in 1492, it came to be called the Arab Mosque because of the Muslims who migrated from Spain were settled in the vicinity of this mosque; and thus the myth that this mosque was originally established before the conquest by Arab Muslims was born. The square planned bell tower of the original church structure, which is in stark contrast with the Turkish architectural style, resembling the minarets of mosques in Syria, and particularly, those of the Umayyad Mosque in Damascus, were all factors that gave credence to this story.

Muslim prisoners and slaves were also present in Constantinople, the capitol of the Byzantine Empire. al-Maqdisi, a tenth century Islamic geographer, records that upon the request of Maslama ibn ‘Abd al-Malik, who led the third siege of Constantinople during the Umayyad period, the emperor ordered the construction of a residence behind the Hippodrome, opposite his palace. This was known as Dar al-Balat and important Muslim prisoners were housed here. In addition, Muslims gathered and openly worshipped in this building.

While important Muslim captives resided in this building, others were compelled to work in various workshops, they were not forced to eat pork and were generally well-treated. Umar ibn Abd al-Aziz made great efforts to have Muslim prisoners held by the Byzantines released, and as part of these efforts he sent envoys to Emperor Leo III. When Umar ibn Abd al-Aziz questioned the envoy he sent to the emperor, the envoy explained that he had met a Muslim prisoner who was reciting the Qur’an and grinding wheat. The prisoner informed him that they had tried to force him to change his religion, but because he had refused he was blinded with hot iron, subjected to other various forms of torture and spent his life grinding wheat. When Umar ibn Abd al-Aziz heard about this, tears rolled down his cheeks; he wrote a threatening letter to the emperor, demanding the release of this prisoner. The emperor agreed to this request, but news of the prisoner’s death reached Umar ibn Abd al-Azîz. On the request of the envoy, the prisoner’s body was handed over to him.

On another occasion, Umar ibn Abd al-Aziz sent an envoy led by Muhammad ibn Ma‘bad to Emperor Leo III in an attempt to secure the release of Muslims taken prisoner by the Byzantines. The emperor was informed that if he agreed, the Byzantine captives would also be released. However, news of the death of the caliph reached Constantinople during these negotiations. It is reported that Leo III was extremely saddened by the caliph’s death and he spoke with great admiration of Umar ibn Abd al-Aziz.

One of the prominent prisoners in Istanbul was Harun ibn Yahya. In his accounts of Istanbul, Harun ibn Yahya, who had been taken captive in Palestine probably towards the end of the fourth century or the beginning of the fifth century, and brought to Istanbul, speaks of issues regarding Muslim prisoners. Harun ibn Yahya, who describes four prisons in the entrances of the Great Palace located in the center of the city, states that one of these prisons was allocated to the Muslim prisoners, and that a feast was given for Muslim prisoners during the twelve day festival period following the Christmas in a grand hall that was entered by passing through the court of honor. In this feast which was attended by the emperor the food prepared was suitable for Muslims, for example, no pork was served.

Abu Firas al-Hamdani, a member of the Hamdanid dynasty, who was an Arab poet and commander, was also one of the prominent individuals who lived in captivity in Constantinople. Abu Firus, captured by the Byzantines in 962, was taken to Constantinople and remained there until prisoners were exchanged in 966. In al-Rumiyat, which he wrote while in captivity, a work that is comprised of many poems and which virtually acts as a dairy, Abu Firas expresses yearning for his nation, family, friends and freedom.

In 1332, joining a convoy of five hundred people, organized by Princess Bayalun, the wife of Uzbeg Khan and daughter of the Greek emperor, Andronicus III Palaiologos, Ibn Battuta travelled to Istanbul and described the city in which he remained for more than a month in his book The Travels of Ibn Battuta. Ibn Battuta, who explains that they were welcomed with a grand ceremony, that they were allocated a mansion close to Princess Bayalun’s mansion and were allowed to roam around the city as they pleased, being served during their three-day stay food such as chicken, mutton, bread, fish and fruit. Ibn Battuta was received by the emperor and spoke with him for a while. The emperor presented Ibn Battuta with a robe of honor and ordered that he should be given a horse with a magnificent bridle and harness, as well as a mizalle (an umbrella that was a symbol of protection) resembling that which was carried above the emperor’s head. In addition, upon the request of Ibn Battuta, a guide was designated to him for his tour of the city. In accordance with customs, these matters were announced to the public with drums, trumpets and fifes.

We see that many of the dynasty members came to Istanbul to request help from or seek refuge with the Byzantines when there was a struggle for throne in the Seljuk and Ottoman periods. Among such figures are Erbasan (Erbasgan), the brother-in-law of the Seljukid ruler Alparslan, who went to Constantinople with his forces due to falling out with Alparslan, and sought asylum with Emperor Romanos Diogenes IV, and Mansur son of Kutalmış, also sought refuge in Constantinople after being defeated in the battle for sovereignty with Suleyman Shah, the founder of the Anatolian Seljuk state.

The Seljukid chieftain Abu al-Qasim accepted the invitation of the Emperor Alexios I and came to Constantinople because Sultan Malik Shah began pursuing him once he began acting independently in Iznik where Suleyman Shah had left him behind as his regent. Abu al-Qasim received a warm welcome in Constantinople. The Byzantines attempted to extend his stay in Istanbul by various means which included banquets held for him almost every day, and horse and cart races in the hippodrome organized in his honor.

2- The solid silver grating built by Sultan Selim III around the sarcophagus of Abu Ayyub al-Ansari

In their battle for throne, the Anatolian Seljuk Sultan Mas‘ud I (1116-1155) and his brother Malik ‘Arab travelled to Constantinople and requested help from the emperor John II Komnenos.

Sultan Kılıçarslan II went to Constantinople to negotiate with Emperor Manuel Komnenos I, who supported the enemy coalition which included the Zangids and Danishmendids. Here he was welcomed by the Byzantines with great respect and generosity. Banquets were given, and horse races and various kinds of entertainment were organized in his honor. Every day food was sent to the sultan on gold and silver plates, all of which were presented to him as gifts. After remaining in Constantinople for eighty days, the sultan was seated at the emperor’s table. The decorative objects and all the plates on the table were presented as a gift. In addition, one thousand horsemen in the retinue of the sultan were presented with various gifts. A treaty was signed between the emperor and the sultan, and the emperor also gave him financial support. After the treaty was concluded, Kılıçarslan II departed from Constantinople. His brother Shahinshah and Zunnun the Danishmendid, who had been defeated by Kılıçarslan, also travelled to Constantinople to request the support of the Byzantine emperor.

The Anatolian Seljuk sultan Giyath al-Din Kaykhusraw I, who was dethroned in 1196, travelled to Constantinople with his retinue and sought refuge with Alexios Angelos III. During his stay in Constantinople, Kaykhusraw I, who established a close relationship with the emperor, was married to the daughter of Manuel Mavrozomes, one of the leading Byzantine statesmen. When Constantinople was occupied by the Crusaders in 1204, Kaykhusraw I departed from Constantinople, and fled to the castle on an island where his father-in-law lived. At the time, he was accompanied by his children, ‘Izz al-Din Kaykawus and ‘Ala al-Din Kayqubad.

Sultan ‘Izz al-Din Kaykawus II, who was dethroned in 1262, boarded a ship from Antalya with his mother, wife, children (Giyath al-Din Mas‘ud and Rukn al-Din Gayumars), his close supporters and all the valuable belongings they could transport; they sailed to Constantinople. He was warmly welcomed in Constantinople by Emperor Michael Palaiologos VIII, who had regained control of the city from the Crusaders. The emperor, who displayed the necessary respect to the sultan’s children and their companions, also granted them permission to live in Istanbul as they wished and travel around the city freely with escorts. The emperor ordered the preparation of worthy residences in Constantinople for each of them. The sultan’s soldiers and supporters also entered the Byzantine territory and met the emperor in Constantinople. Later, this large group of Turkish people was settled in Dobruja. However, due to his fear of the Ilkhanids, the emperor later imprisoned Kaykawus, his mother, two sons and sister in the Enos (Enez) Castle at the mouth of the Maritsa River. One of the Sultan’s younger sons, who was kept in Constantinople, was converted to Christianity and given the name Malik Constantine. Kaykawus’ men and commanders were taken to Hagia Sofia, and forced to accept the Christian faith. Those who refused to do so were killed. ‘Izz al-Din Kaykawus and his sons were rescued by Berke Khan, ruler of the Golden Horde.

During the Ottoman period, Orhan Bey supported his father-in-law John VI Kantakouzenos, thus securing the Byzantine throne for him. Later Orhan Bey and his wife Theodora travelled to Scutari (Üsküdar) where further negotiations culminating in a peace treaty were held. According to the treaty signed between Sultan Murad I and Emperor Andronikos Palaiologos in 1376, the emperor agreed to protect the rights of Muslims living in Constantinople and to appoint a judge to deal with their claims. On the request of Bayezid I (1389-1402), a Turkish neighborhood was established, which also included a mosque. After Yıldırım Bayezid’s first siege on Constantinople in 1391, which lasted seven months, Emperor Manuel II offered to conclude a truce out of desperation. According to the truce treaty, the emperor agreed to establish a Muslim neighborhood, allocating seven hundred houses to Muslims in what is today Sirkeci, a mosque would be constructed in this neighborhood, and a qadi would be appointed by the Ottomans to settle any disputes that arose among the Muslims, or to judge their claims against the Byzantines. In this period, the majority of the Muslim population consisted of those who had come to the city for trade. Although Emperor Manuel initially did not comply with the stipulations of the agreement, after Bayezid’s third siege of Constantinople, he was eventually forced to fulfill the obligations of the treaty. Seven hundred homes mentioned in the treaty were indeed allocated to the Turkish population and a mosque was built in the neighborhood. Families were transported here from the shores of Taraklı and Göynük by Bayezid I, and settled in this district. Bayezid I also appointed an imam and qadi for the population.

3- The tomb of Abu Shayba al-Khudri

Taking advantage of the throne struggles between the Ottoman princes after Bayezid’s defeat before Timur in the Battle of Ankara, Manual II Palaiologos closed the qadi court and the mosque, and also eliminated the trade concessions he had previously granted to the Muslims. Suleyman Çelebi (Emir Suleyman), the son of Bayezid I, travelled to Constantinople, and gained the support of Emperor II Manuel. He left his young brother Kasım Çelebi and his sister Fatma Sultan hostage in Constantinople and travelled to Edirne, where he declared his sultanate. Bayezid’s other sons, Mehmed Çelebi, ‘Isa Çelebi and Mustafa Çelebi (Mustafa the Impostor), as well as Shahzada Mustafa (Mustafa the Young), the son of Mehmed I, travelled to Constantinople and sought refuge with Emperor Manuel II Palaiologos in their battle for the throne; they gained military support after spending a certain amount of time in the city. Although Constantinople was besieged by Musa Çelebi in 1411, and once more by Murad II in 1422, neither of them was successful. The last Byzantine emperors John Palaiologos and Constantine XI Palaiologos both provoked and supported Orhan Çelebi in the battle for the throne against Murad II and later his son Mehmed II. In 1453, Mehmed II sent Mahmud Pasha as an envoy to Emperor Constantine XI, asking him to hand over control of the city; this offer was rejected. The siege he laid to the city ended in the conquest of Constantinople on 23 May, 1453, when the city came under Muslim sovereignty and the Byzantine Empire became history.


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This article was translated from Turkish version of History of Istanbul with some editions to be published in a digitalized form in 2019.

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