When al-Muʿtaṣim succeeded his brother al-Maʾmūn as caliph, the Emperor of Constantinople, Theophilos, decided to conclude a peace treaty with the Muslims. For this purpose, a delegation headed by Yuhanna al-Nahwi—one of the greatest scholars of that era who was fluent in Arabic—was sent to Baghdad to meet with al-Muʿtaṣim. This delegation, which brought valuable gifts, had two main objectives: first, to establish a permanent peace treaty between the Caliph and the Byzantine Emperor, and second, to repatriate Manuel, a Byzantine commander who had taken refuge at the Abbasid court. While the delegation succeeded in fulfilling the second goal, it failed to achieve the first. As a result, al-Muʿtaṣim chose instead to release one hundred Christian prisoners in order to somewhat appease the Emperor.
Following the failure of the peace negotiations, Theophilos launched an attack on the border town of Zibatrah, capturing and destroying it and massacring many of its inhabitants. He also ignored al-Muʿtaṣim’s appeal to cease the bloodshed. In response, al-Muʿtaṣim declared war and marched towards Byzantine territories, laying siege to Amorium—the largest city of the Romans in Asia Minor. After several failed assaults and strong resistance from the Byzantines, al-Muʿtaṣim decided to maintain the siege until the city fell.
The emperor sent another request for peace, but al-Muʿtaṣim rejected it and detained the envoys. The siege lasted fifty-five days, and eventually, the city was captured by the Muslims. Unlike Theophilos, al-Muʿtaṣim refrained from excessive cruelty and violence, although he did punish the Christians and destroy the city. He then released the envoys so they could report his victory to the emperor, saying: “Tell your master that I have repaid the debt of Zibatrah.” This event occurred in 223 AH (838 CE). The conflict between the Abbasid Caliphate and the Byzantine Empire continued for another century. During the reign of Constantine VII, who was still a child and ruled under the regency of his mother Queen Zoe Karbonopsina, the court of Constantinople dispatched an envoy to Caliph al-Muqtadir bi-llāh, requesting peace and the ransom of prisoners.
Islamic historians narrate the events of this embassy: two Roman ambassadors arrived in Baghdad in the month of Muharram, 305 AH, and were received with honor. They were ceremoniously taken to the vizier and delivered the Emperor’s letter. Afterwards, they were escorted with the same dignity to the Caliph, where they presented their diplomatic mission.
The Caliph accepted the Emperor’s request to release the prisoners and appointed his special aide Mūnis to oversee the process. He sent Mūnis with an army to act as governor of every city he entered, fulfill the mission as he wished, and then depart. He also gave him 120,000 dinars to ransom Muslim prisoners in exchange.
Mūnis fulfilled his mission and succeeded in freeing thousands of captives. This prisoner exchange led to several other diplomatic missions between the two sides throughout the 3rd century AH and resulted in some peaceful agreements. During Queen Zoe’s time, the Roman governor of Calabria (Qalūriyya) sent his envoys to the Fatimid Caliph of Egypt, and a treaty was signed. According to the treaty, the Byzantine government pledged to pay annual tribute to the Fatimid Caliph, who in turn promised to restrain Muslim rulers in Sicily from launching attacks on Calabria. These treaties continued for some time.
Islamic diplomacy in Muslim Spain held a prominent position, owing to its strategic location by both land and sea at the gates of Christian Europe, as well as its extensive trade and political relations with many Christian states.
During the reign of ʿAbd al-Raḥmān al-Nāṣir, diplomatic relations between Islam and major Christian powers reached their peak, with delegations and embassies frequently arriving in al-Andalus. In the month of Ṣafar, 336 AH (948 CE), representatives of Constantine VII, known as Porphyrogennetos, arrived at ʿAbd al-Raḥmān al-Nāṣir’s court bearing valuable gifts. Al-Nāṣir welcomed them with great ceremony. They presented a letter from the Emperor, written in Greek.
The letter bore a golden seal, with an image of Jesus Christ on one side and a finely crafted, multicolored portrait of the emperor on the other.
The translation of the emperor’s letter was as follows: “From Constantine and Romanus (Romanos II, son of Constantine), faithful to Christ and two great kings of Rome, to the one deserving of great honor, the noble and dignified: Abd al-Rahman, Caliph and ruler over the Arabs in Al-Andalus. May God preserve him.”
The emperor’s envoys were deeply impressed by the splendor and majesty of the Caliph and his court. Prominent figures of Islam delivered public speeches, among them the eloquent judge Mundhir ibn Saʿīd al-Ballūṭī, who delivered an impromptu oration praising the deeds of ʿAbd al-Raḥmān al-Nāṣir and even composed a poetic tribute on the spot.
When the imperial envoys departed, ʿAbd al-Raḥmān al-Nāṣir sent his ambassador Hishām ibn Hadhīl with them, along with precious gifts, to reinforce the bonds of friendship and alliance. The mission returned two years later, having strengthened diplomatic ties. Afterward, envoys from various Christian rulers arrived at ʿAbd al-Raḥmān’s court, including those from Peter Prsemion (King of the Slavs/Bulgaria), the Holy Roman Emperor Otto I, and the King of France.
Abd al-Rahman welcomed them as he had the Eastern Roman envoys and held celebrations in their honor. He also sent Rabīʿ, the bishop of Rīf, with the Slavic delegation to their king. Later, representatives of Pope John XII were sent to seek the goodwill of the Caliph of the Muslims.
Islamic diplomacy, like the best examples of modern diplomacy, did not neglect the use of covert elements. Past Islamic caliphs, in addition to public envoys and messengers who gathered information from their provinces, employed secret agents tasked with monitoring the courts and governments of foreign powers, reporting anything that could help or harm the Caliph’s administration.
It appears that the Abbasids were the first in Islam to organize such covert diplomacy. Caliphs like al-Mahdī, Hārūn al-Rashīd, al-Maʾmūn, and al-Muʿtaṣim had spies in Constantinople and other capitals to remain informed about the activities of the Roman Emperor and other rulers.
These spies were often chosen from various social classes, especially merchants, and carried out their duties with great skill. This diplomatic system reached its peak during the height of the Abbasid Caliphate, when the Caliph enjoyed full power and independence.
However, with the decline of the caliphs’ power during the rule of Turkish guards and the Buyids, this spy network weakened—especially as the Caliph became a symbolic figure confined to his palace and stripped of real authority. After the fall of the Abbasid Caliphate and the emergence of independent local rulers in its former provinces, the role of covert agents shifted to that of open envoys, working in courts such as Cairo, Damascus, Mosul, Nishapur, Merv, and others. These diplomats not only engaged in foreign affairs but often accompanied rulers in military campaigns. There are records of them being alongside Alp Arslan and Malikshah, sometimes even participating in internal affairs or mediating disputes.
Islamic religious policy varied across eras and dynasties. However, generally speaking, Islamic governments have shown tolerance towards their non-Muslim subjects since the early days of Islam. A historical document proves this: in 1138 CE, the Abbasid Caliph al-Muktafī issued a decree granting full religious freedom to his Nestorian Christian subjects, including Patriarch Abdishoʿ.
Dr. Mingana, the librarian of the Reynolds Library, who discovered this document, wrote: “We have always needed a document that clarifies the political relations between Islam and Christianity in an era when Islam had the power of life and death over millions of Christian subjects. Although some caliphs—like al-Mutawakkil—issued cruel decrees against Christians, such events must be considered violations of official policy, and their perpetrators as lawbreakers.”
This official Islamic position is clearly demonstrated in the surviving document, which firmly rejects any systematic oppression as part of Islam’s official policy. Dr. Mingana further writes: “This document was issued from the Caliph’s own court. But could the King of England, the Queen of the Netherlands, or the President of France be more lenient toward their Muslim subjects than this? The Qur’an does not inspire oppression against Christians, just as the Gospel was not the source of the brutalities committed by the Inquisition.”
From the above, we conclude that diplomacy in Islamic states was not significantly different from that of Christian states in the medieval period in terms of protocol and tradition. This indicates that the administrative systems and political customs of the East and West in those eras were, in several respects, quite similar.
