Al - Mundhir III ibn al - Harith Al - Mundhir ibn al - Ḥārith ( ) , known in Greek sources as ( Flavios ) Alamoundaros ( ) , 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 " . Despite his victories over the rival Persian - backed Lakhmids , throughout Mundhir ' s reign his relations with Byzantium were lukewarm due to his staunch Monophysitism . This led to a complete breakdown of the alliance in 572 , after Mundhir discovered Byzantine plans to assassinate him . Relations were restored in 575 and Mundhir secured from the Byzantine emperor both recognition of his royal status and a pledge of tolerance towards the Monophysite Church . In 580 or 581 , Mundhir participated in an unsuccessful campaign against the Persian capital , Ctesiphon , alongside the Byzantine general ( and future emperor ) Maurice . The failure of the campaign led to a quarrel between the two and Maurice accused Mundhir of treason . Byzantine agents captured Mundhir , who was brought to Constantinople but never faced trial . His arrest provoked an uprising among the Ghassanids under Mundhir ' s son al - Nu ' man VI . When Maurice ascended the throne in 582 , Mundhir was exiled to Sicily although , according to one source , he was allowed to return to his homeland after Maurice ' s overthrow in 602 . Mundhir was the last important Ghassanid ruler ; in 584 , the Byzantines would break up the Ghassanid federation . A capable and successful military leader , his rule also saw the strengthening of Monophysitism and a cultural flowering among the Arabs under his rule . Biography . Succession and early career . 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 . 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 . 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 . Mundhir had been confirmed as his father ' s heir as early as 563 , during the latter ' s visit to Constantinople , and succeeded after Harith ' s death in 569 . It appears that Mundhir inherited his father ' s Byzantine titles one at a time , as they were not hereditary : the rank of " patricius " , the honorific appellation " paneuphemos " ( most honorable ) and the prestigious honorific " gentilicum " " Flavius " , borne by the Byzantine emperors and consuls . Soon after Harith ' s death , Ghassanid territory was attacked by Qabus ibn al - Mundhir , the new Lakhmid ruler , who sought to take advantage of the situation . Qabus ' s forces were repulsed and Mundhir invaded Lakhmid territory in turn , seizing much plunder . As he turned back , the Lakhmids again confronted the Ghassanid army , but suffered a heavy defeat . After this success , Mundhir wrote to the Byzantine emperor Justin II ( r . 565 – 578 ) asking for gold for his men . This request reportedly angered Justin , who sent instructions to his local commander to lure the Ghassanid ruler into a trap and have him killed . But the letter fell into Mundhir ' s hands , who then severed his relations with the Empire and refused to commit his forces during the war with Persia that began in 572 . Return to Byzantine allegiance . As the Byzantines relied upon the Ghassanids to cover the approaches to Syria , Mundhir ' s withdrawal left a gap in the Byzantine southern flank , which persisted for three years until 575 when Mundhir returned to the Byzantine allegiance through the mediation of the general Justinian , who met Mundhir at Sergiopolis . 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 . The city was sacked , plundered , and put to the torch , except for the churches . According to John of Ephesus , Mundhir donated much of his booty from this expedition to monasteries and the poor . 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 . The war with Persia was interrupted by a three - year truce agreed in 575 . In 578 , hostilities were renewed , but the sources on the period , fragmentary as they are , do not mention any Ghassanid participation for the first two years . In 580 , Mundhir was invited by Emperor Tiberius II ( r . 578 – 582 ) to visit the capital again . He arrived in the city on 8 February , accompanied by two of his sons , and was lavishly received . On this occasion , among a multitude of other gifts , he was also presented with a royal crown , instead of the simpler coronet or diadem he had been awarded before . While at Constantinople , Mundhir received permission from the emperor to hold a Monophysite church council , which convened on 2 March 580 . This council managed , albeit for a brief time , to reconcile the various factions and sects of the Monophysites . It was a goal towards which Mundhir had long striven , as when he intervened in the quarrel between Jacob Baradaeus and Paul the Black , the Monophysite patriarch of Antioch . Before leaving the imperial capital , the Ghassanid ruler also secured a pledge from the emperor that the persecutions of the Monophysites would cease . When he returned home , Mundhir discovered that the Lakhmids and Persians had used his absence to raid his domains . Gathering his forces , he fell upon their army , defeated them , and returned home laden with booty . 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 . The combined force moved south along the river , accompanied by a fleet of ships . The allied army stormed the fortress of Anatha and moved on until it reached the region of Beth Aramaye in central Mesopotamia , near the Persian capital of Ctesiphon , but there they found the bridge over the Euphrates destroyed by the Persians . 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 . The retreat was arduous for the exhausted army , and Maurice and Mundhir exchanged recriminations for the expedition ' s failure . Mundhir and Maurice cooperated however in forcing Adarmahan to withdraw , and defeated him at Callinicum . Upon returning to his lands , Mundhir learned that a combined Persian - Lakhmid force was preparing another attack against the Ghassanid realm . Immediately he set out to meet them , engaged their army and comprehensively defeated it , before going on to capture the enemy camp . It was to be his last victory . Arrest and exile . Despite his successes , Mundhir was accused by Maurice of treason during the preceding campaign . Maurice claimed that Mundhir had revealed the Byzantine plan to the Persians , who then proceeded to destroy the bridge over the Euphrates . The chronicler John of Ephesus explicitly calls this assertion a lie , as the Byzantine intentions must have been plain to the Persian commanders . Both Maurice and Mundhir wrote letters to Emperor Tiberius , who tried to reconcile them . Finally , Maurice himself visited Constantinople , where he was able to persuade Tiberius of Mundhir ' s guilt . The charge of treason is almost universally dismissed by modern historians ; Irfan Shahîd says that it probably had more to do with Maurice ' s dislike of the veteran and militarily successful Arab ruler . This was further compounded by the Byzantines ' habitual distrust of the " barbarian " and supposedly innately traitorous Arabs , as well as by Mundhir ' s staunchly Monophysite faith . Tiberius ordered Mundhir ' s arrest , and a trap was laid for the Ghassanid king : summoned to Constantinople to answer charges of treason , Mundhir chose his friend , the " curator " Magnus , as his advocate . Magnus was probably a Byzantine , hailing from Huwwarin ( Evaria ) . There he had built a church , and he now called on Mundhir to join him and the patriarch of Antioch Gregory in the dedication ceremony . Mundhir arrived with only a small escort and was arrested by Byzantine troops stationed in secret at the location . He was transported to Constantinople , joined along the way by his wife and three of his children . At the capital , he was treated well by Tiberius , who allowed him a comfortable residence and a subsidy , but denied him an audience . Irfan Shahîd believes that this generous treatment , as well as the fact that he was not brought to trial for his supposed treason , indicate that Tiberius too did not believe the charges , but ordered the arrest chiefly to placate the strong anti - Monophysite faction in the imperial capital . 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 . For two years , the Ghassanid army launched raids into the Byzantine provinces from their bases in the desert , even defeating and killing the Byzantine " dux " of Arabia in a battle at Bostra . Tiberius reacted by raising a Chalcedonian brother of Mundhir to the Ghassanid kingship . A large army with Magnus at its head was dispatched east to counter Nu ' man and install his uncle as king . The latter was swiftly done , but the new king died after only twenty days . Magnus also had some success in subduing or subverting the allegiance of some minor Arab tribes away from the Ghassanids . 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 . Instead , he too was arrested , tried , and sentenced to death , quickly commuted to house arrest . Mundhir remained in Constantinople until the death of Tiberius and the accession of Maurice , when he was exiled to Sicily . It is likely that he is the man Pope Gregory the Great mentioned as " Anamundarus " in 600 , indicating that he was still alive at the time . A 13th - century Syriac chronicle further records that after Maurice ' s overthrow and murder in 602 , Mundhir was allowed to return home . Legacy . Mundhir in many ways continued in the footsteps of his father . 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 . Despite his fervent dedication to Monophysitism , he remained loyal to Byzantium as the Christian state " par excellence " ; as Irfan Shahîd comments , Mundhir ' s self - image may well have been that of a " sixth - century Odenathus fighting for the Christian Roman Empire , as his third - century predecessor had done for the pagan empire " . Yet , in the end , his independent character and his role as the protector of the Monophysite Church led to his downfall and exile . 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 . Mundhir ' s arrest was followed after 584 by the dissolution of the Ghassanid federation into a number of smaller chiefdoms . 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 . 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 " . The Ghassanids left an important cultural legacy as well . Their patronage of the Monophysite Syrian Church was crucial for its survival and revival , and even its spread , through missionary activities , south into Arabia . According to the historian Warwick Ball , the Ghassanids ' promotion of a simpler and more rigidly monotheistic form of Christianity in a specifically Arab context can be said to have anticipated Islam . 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 . The surviving descriptions of the Ghassanid courts impart an image of luxury and an active cultural life , with patronage of the arts , music and especially Arab - language poetry . In the words of Ball , " the Ghassanid courts were the most important centres for Arabic poetry before the rise of the Caliphal courts under Islam " , and their court culture , including their penchant for desert palaces like Qasr ibn Wardan , provided the model for the Umayyad caliphs and their court . Among the architectural remains from Mundhir ' s own reign are the castle of Dumayr and the so - called " ecclesia extra muros " ( nowadays identified as Mundhir ' s own audience hall or " praetorium " ) in Sergiopolis , where an inscription in Greek , celebrating Mundhir , survives . 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 .