Al-Mundhir ibn al-Ḥārith (المنذر بن الحارث), known in Byzantine sources as Flavios Alamoundaros (Φλάβιος Ἀλαμούνδαρος), was the king of the Ghassanid Arabs from 569 to circa 581.
A son of al-Harith ibn Jabalah, he succeeded his father both in the kingship over his tribe and as the chief of the Byzantine Empire's Arab clients and allies in the East, with the rank of patricius.
Mundhir was the son of al-Harith ibn Jabalah, ruler of the Ghassanid tribe and supreme phylarch of the Arab foederati in the eastern frontier of the Byzantine Empire.
[1] Situated on the southern flank of the frontier, the Ghassanids faced the Lakhmids, another powerful Arab tribe who were in turn the chief client of Byzantium's main antagonist, the Sassanid Persian Empire.
[2] Harith had been raised to the kingship and to the position of supreme phylarch by the Byzantine emperor Justinian I (r. 527–565), who wished thereby to create a strong counterpart to the Lakhmid rulers.
[8] Immediately after this reconciliation, Mundhir assembled an army in secret and launched an attack against Hirah, the Lakhmid capital, arguably the Arab world's largest, richest, and most culturally vibrant city at the time.
[7][10] The same year, Mundhir visited Constantinople, where he was awarded a crown or diadem (stemma), marking the formal renewal of his role as Byzantium's chief Arab client-king.
[15][17] In the summer of 580 or 581, Mundhir went to Circesium on the river Euphrates, where he joined the Byzantine forces under the new magister militum per Orientem, Maurice, for a campaign deep into Persian territory.
[19] With any possibility of a march to Ctesiphon gone, they were forced to retreat, especially since at the same time the Persian commander Adarmahan had taken advantage of the Byzantine army's absence and was raiding freely in Osroene, where he sacked the provincial capital Edessa.
[26] In the meantime, Mundhir's arrest provoked a revolt led by his four sons, especially the eldest, Nu'man, a man described by John of Ephesus as even more capable and warlike than his father.
Magnus died shortly before Tiberius's own death in August 582, and with Maurice's accession to the throne, Nu'man journeyed to Constantinople to achieve a reconciliation with Byzantium.
He was a militarily successful ally of the Byzantines, especially against his fellow Arabs, the Lakhmid tribesmen, and secured Byzantium's southern flank and its political and commercial interests in Arabia proper.
In the overwhelmingly pro-Chalcedonian atmosphere of Tiberius's and Maurice's reigns, unlike his father Harith, who was protected by Empress Theodora's Monophysite leanings, Mundhir could not count on any influential support in Constantinople.
This was a momentous event in the history of Byzantine-Arab relations: it destroyed Byzantium's "protective shield" against incursions from the Arabian desert, an error for which the Byzantines would pay dearly with the onset of the Muslim conquests.
It was paralleled a few years later by the destruction of the Lakhmid kingdom at the hands of the Persians, opening a power vacuum in northern Arabia which the nascent Muslim state would later fill.
[34] On the other hand, the Muslim conquests, and before them the destructive thirty-year war with Persia, were still a long way off in 584, and the dissolution of the Ghassanid federation may be seen simply, according to the historian Michael Whitby, as the elimination of an "over-successful quasi-client neighbour", who threatened to become "too powerful for the good of its supposed patron".
[36] Ghassanid rule also brought a period of considerable prosperity for the Arabs on the eastern fringes of Syria, as evidenced by a spread of urbanization and the sponsorship of several churches, monasteries and other buildings.
Sergiopolis (modern Rusafa) was a site of particular significance due to the popularity of the cult of Saint Sergius among the Arabs, and was also a focus of later Umayyad building activity.