Campaign of the Byzantines against Samosata, 859

1. Historical background

The young emperor of Byzantium Michael III (842-867) seized the throne almost with a coup, with the aid of his uncle, the caesar Vardas, in 856,1 an event which marked a new phase in the struggle against the Arabs on the eastern front, in order to secure the Byzantine domination in Asia Minor. For the first time, however, operations against the Arabs were combined with the religious policy of the Empire. More specifically, in the framework of a strict orthodox policy which was enforced after the final restoration of the icons, the persecutions against the Paulicians were intensified, the formers now treated as enemies of the whole empire. The immediate danger of extinction forced the Paulicians to move towards the east, in the area of Upper Euphrates. The emir of Melitene, Amr al-Aqta’ ceded them the area north of Melitene, where they settled, offering in exchange their military services to the Arabs against the Byzantines. Thus, the campaign of Petronas, strategos of the thema of Thrakesion, at the end of summer 856, with which the new period of Byzantine attacks begins, was aimed towards the Arabs, as well as towards the Paulicians. Nevertheless, notwithstanding the victorious outcome of the campaign, the Arabs continued their military operations in Asia Minor.2 The campaign which in 859 the emperor Michael III and Caesar Vardas made in the region of Upper Euphrates forms part of these conflicts.

2. Conduct and outcome of the expedition

Leading a large military force, the young Michael III and the brother of his mother Caesar Vardas, started together, in the spring of 859 a campaign against the Arabs.3 They set as a target the advance of their troops in the region of the river Euphrates until the powerful fortress of Samosata, which was in the hands of the Arabs as early as the 7th century. Such an eastern advance of the Byzantine army presented dangers for the security of the troops, but also for the defence of the empire itself, in case the Byzantines suffered a military defeat. With this on his mind, Michael III strengthened the defence of the cities in which the Byzantine army could seek refuge after a possible defeat; in the same year he rebuilt the fortifications of Ankara,4 which were destroyed in 838 during the campaign of the Arab caliph al-Mu’ tasim (833-842) against Amorion, whereas as early as 858 he had already renovated the walls of Nicaea.5

Having their back covered, Michael III and Vardas moved towards the region of Upper Euphrates achieving military victories. When they finally reached Samosata, they attempted to seize the city, the siege of the city, however, brought no result and the imperial forces returned to the imperial territory.6

3. Results of the campaign

The victorious campaign of Michael III and Vardas in 859 uplifted the moral of the Byzantines, already high after the successful campaign of Petronas in 856, in the struggle with the Arabs even more. Nonetheless, it brought no significant gains for the empire since the Arabs, aided by the Paulicians, continued their military activity against Byzantium.7 However, thanks to this specific campaign, the emperor strengthened the defence of Asia Minor by restoring the damages afflicted to the fortifications of Nice and Ankara by the previous Arab raids.



1. Michael, aided by his uncle Vardas, organized the assassination of Theoktistos, the most trusted associate of the regent Empress Theodora and one of the regents of the Emperor himself. Under these conditions Theodora was forced to offer the throne to her son, whereas her daughters became nuns and, two years later, she followed them to the monastery.

2. In order to avenge the damage infliged by general Petronas, the emir of Melitene Amr asked immediately from the emir of Tarsus Ali to raid the Byzantine Empire during the winter (856-857), whereas in 858 the Arabs took successfully the offensive in western Cappadocia and captured the fort of Semalouos.

3. Χριστοφιλοπούλου Αικατερίνη, Βυζαντινή Ιστορία 2/1: 610-8672 (Θεσσαλονίκη 1993), p. 211 notes that, although Michael III took personally part in this campaign, he was not the one actually commanding the troops; his uncle Vardas was.

4. Five inscriptions in verse are preserved, which praise Emperor Michael III for the restoration of the walls of Ankara. One of them mentions the date 10th June 859.

5. A relative inscription, which is dated to the year of 858, is preserved on one of the towers of the walls of Nicaea.

6. Arab sources mention this specific campaign of the Byzantines as successful. They also mention that, during a raid, the Byzantines killed and captured 500,000 Arabs. In contrast, the Theophanes Continuatus, Χρονογραφία, ed. I. Bekker, Theophanes Continuatus (Bonn 1838) 176, 7-177, 5, Ιωσήφ Γενέσιος, Βασιλείαι, ed. A. Lesmuller-Werner – I. Thurn, Ioesphi Genesii Regum Libri Quattuor (Corpus Fontium Historiae Byzantinae 14, Berlin-New York 1978) 65, 14-21, and Ιωάννης Σκυλίτζης, Σύνοψις Ιστοριών, ed. I. Thurn, Ioannis Scylitzae Synopsis Historiarum (Corpus Fontium Historiae Byzantinae 5, Berlin-New York 1973) 98, 84-99, 7 report a defeat of the Byzantine army, with heavy losses during the siege of Samosata, where they also mention that Michael III himself was almost captured by the Arabs. Modern scholars consider this information unreliable, attributing it to the negative light under which Byzantine sources portray Emperor Michael III to the propaganda in favour of the subsequent emperor Basil I and the Macedonian dynasty.

7. Ostrogorsky, G., Geschichte des byzantinischen Staates, transl. By Παναγόπουλος, Ι., Ιστορία του βυζαντινού κράτους, vol. 2 (Αθήνα 1989), (first published in German, Munchen 1963), p. 101. Almost simultaneously with the campaign of the Byzantines in the region of Upper Euphrates, the emir of Tarsus Ali was causing troubles in the Arab-Byzantine frontier of the area of Cappadocia, resulting in an uprising of the inhabitants of Loulos, who were mostly Slavs, and surrender this frontier fort to the Arabs.