Byzantine – Sasanian War of 572 – 591 The Byzantine – Sasanian War of 572 – 591 was a war fought between the Sasanian Empire of Persia and the Eastern Roman Empire , termed by modern historians as the Byzantine Empire . It was triggered by pro - Byzantine revolts in areas of the Caucasus under Persian hegemony , although other events contributed to its outbreak . The fighting was largely confined to the southern Caucasus and Mesopotamia , although it also extended into eastern Anatolia , Syria , and northern Iran . It was part of an intense sequence of wars between these two empires which occupied the majority of the 6th and early 7th centuries . It was also the last of the many wars between them to follow a pattern in which fighting was largely confined to frontier provinces and neither side achieved any lasting occupation of enemy territory beyond this border zone . It preceded a much more wide - ranging and dramatic final conflict in the early 7th century . Outbreak of war . Less than a decade after the fifty - year peace treaty of 562 , tensions mounted at all points of intersection between the two empires ' spheres of influence , as had happened before when war broke out in the 520s . In 568 – 569 , the Byzantines were engaged in ultimately abortive negotiations ( cf . the embassy of Zemarchus ) with the Gokturks for an alliance against Persia ; in 570 , the Sassanids invaded Yemen , expelling the Byzantines ' Aksumite allies and restoring the Himyarite Kingdom as a client state ; in 570 and 571 , the Sassanids ' Arab clients , the Lakhmids launched raids on Byzantine territory , although on both occasions they were defeated by the Ghassanids , clients of the Byzantines ; and in 570 , the Byzantines made a secret agreement to support an Armenian rebellion against the Sassanids , which began in 571 , accompanied by another revolt in Iberia . Early in 572 , the Armenians under Vardan II Mamikonian defeated the Persian governor of Armenia and captured his headquarters at Dvin ; the Persians soon retook the city but shortly afterwards it was captured again by combined Armenian and Byzantine forces and direct hostilities between Byzantines and Persians began . Despite frequent revolts in the 5th century , during the earlier wars of the 6th century the Armenians had largely remained loyal to their Sassanid overlords , unlike their neighbours and fellow Christians in Iberia and Lazica . By joining the Iberians , Lazi , and Byzantines in a coalition of the region ' s Christian peoples , the Armenians dramatically shifted the balance of power in the Caucasus , helping Byzantine forces to carry the war deeper into Persian territory than had previously been possible on this front : throughout the war , Byzantine forces were able to invade as far as Albania ( modern Azerbaijan ) and even wintered there . Fall of Dara . In Mesopotamia , however , the war began disastrously for the Byzantines . After a victory at Sargathon in 573 , they laid siege to Nisibis and were apparently on the point of capturing this , the chief bulwark of the Persian frontier defences , when the abrupt dismissal of their general Marcian led to a disorderly retreat . Taking advantage of Byzantine confusion , Sassanid forces under Khosrau I ( r . 531 – 579 ) swiftly counter - attacked and encircled Dara , capturing the city after a four - month siege . At the same time , a smaller Persian army under Adarmahan ravaged Syria , sacking Apamea and a number of other cities . To make matters worse , in 572 the Byzantine emperor Justin II ( r . 565 - 578 ) had ordered the assassination of the Ghassanid king al - Mundhir III ; as a result of the unsuccessful attempt on his life , al - Mundhir severed his alliance with the Byzantines , leaving their desert frontier exposed . The fall of Dara , the main Byzantine stronghold in Mesopotamia , reportedly drove Justin II to insanity , and control of the Byzantine Empire passed to his wife Sophia and Tiberius Constantine . The new regents agreed to pay 45 , 000 " nomismata " for a one - year truce , and later in the year extended this to five years , secured by an annual payment of 30 , 000 " nomismata " . However , these truces applied only to the Mesopotamian front ; in the Caucasus , the war continued . Khosrau I ' s last campaign . In 575 , the Byzantines managed to settle their differences with the Ghassanids ; this renewal of their alliance at once bore dramatic fruit as the Ghassanids sacked the Lakhmid capital at Hira . In the same year , Byzantine forces took advantage of the favourable situation in the Caucasus to campaign in Caucasian Albania and secure hostages from the native tribes . In 576 , Khosrau set out on what was to be his last campaign and one of his most ambitious , staging a long - range strike through the Caucasus into Anatolia , where Persian armies had not been since the time of Shapur I ( r . 240 / 242 – 270 / 272 ) . His attempts to attack Theodosiopolis and Caesarea were thwarted , but he managed to sack Sebasteia before withdrawing . On the way home , he was intercepted and severely defeated near Melitene by Justinian , the " magister militum " of the East ; pillaging the undefended city of Melitene as they fled , his army suffered further heavy losses as they crossed the Euphrates under Byzantine attack . Khosrau was reportedly so shaken by this fiasco and his own narrow escape that he established a law forbidding any of his successors from leading an army in person , unless to face another monarch also campaigning in person . The Byzantines exploited Persian disarray by raiding deep into Caucasian Albania and Azerbaijan , launching raids across the Caspian Sea against northern Iran , wintering in Persian territory and continuing their attacks into the summer of 577 . Khosrau now sued for peace , but a victory in Armenia by his general Tamkhosrau over his recent nemesis Justinian stiffened his resolve and the war continued . War returns to Mesopotamia . In 578 , the truce in Mesopotamia came to an end and the main focus of the war shifted to that front . After Persian raids in Mesopotamia , the new " magister militum " of the East Maurice mounted raids on both sides of the Tigris , captured the fortress of Aphumon and sacked Singara . Khosrau again sought peace in 579 , but died before an agreement could be reached and his successor Hormizd IV ( r . 579 – 590 ) broke off the negotiations . In 580 , the Ghassanids scored yet another victory over the Lakhmids , while Byzantine raids again penetrated east of the Tigris . However , around this time the future Khosrau II was put in charge of the situation in Armenia , where he succeeded in convincing most of the rebel leaders to return to Sassanid allegiance , although Iberia remained loyal to the Byzantines . The following year , an ambitious campaign along the Euphrates by Byzantine forces under Maurice and Ghassanid forces under al - Mundhir III failed to make progress , while the Persians under Adarmahan mounted a devastating campaign in Mesopotamia . Maurice and al - Mundhir blamed each other for these difficulties , and their mutual recriminations led to al - Mundhir ' s arrest in the following year on suspicion of treachery , triggering war between Byzantines and Ghassanids and marking the beginning of the end of the Ghassanid kingdom . Stalemate . In 582 , after a victory at Constantina over Adarmahan and Tamkhosrau in which the latter was killed , Maurice was acclaimed emperor following the death of Tiberius II Constantine ( r . 574 – 582 ) . The advantage gained at Constantina was lost later in the year when his successor as " magister militum " of the East , John Mystacon , was defeated on the river Nymphios by Kardarigan . During the mid - 580s , the war continued inconclusively through raids and counter - raids , punctuated by abortive peace talks ; the one significant clash was a Byzantine victory at the Battle of Solachon in 586 . The arrest by the Byzantines of al - Mundhir ' s successor al - Nu ' man in 584 led to the fragmentation of the Ghassanid kingdom , which reverted to a loose tribal coalition and never regained its former power . In 588 , a mutiny by unpaid Byzantine troops against their new commander , Priscus , seemed to offer the Sassanids a chance for a breakthrough , but the mutineers themselves repulsed the ensuing Persian offensive ; after a subsequent defeat at Tsalkajur , the Byzantines won another victory at Martyropolis . During this year , a group of prisoners taken at the fall of Dara 15 years earlier reportedly escaped from their prison in Khuzestan and fought their way back to Byzantine territory . Civil War in Persia . In 589 , the course of the war was abruptly transformed . In spring , the Byzantine pay dispute was settled , bringing an end to the mutiny , but Martyropolis fell to the Persians through the treachery of an officer named Sittas and Byzantine attempts to retake it failed , although the Byzantines won a battle at Sisauranon later in the year . Meanwhile in the Caucasus , Byzantine and Iberian offensives were repulsed by the Persian general Bahram Chobin , who had recently been transferred from the Central Asian front where he had brought a war with the Gokturks to a successful conclusion . However , after he was defeated by the Byzantines under Byzantineus on the river Araxes , Bahram was contemptuously dismissed by Hormizd IV . The general , enraged at this humiliation , raised a revolt which soon gained the support of much of the Sassanid army . Alarmed by his advance , in 590 members of the Persian court overthrew and killed Hormizd , raising his son to the throne as Khosrau II ( r . 590 – 628 ) . Bahram pressed on with his revolt regardless and the defeated Khosrau was soon forced to flee for safety to Byzantine territory , while Bahram took the throne as Bahram VI , marking the first interruption of the Sassanid dynasty ' s rule since their empire ' s foundation . With support from Maurice , Khosrau set out to regain the throne , winning the support of the main Persian army at Nisibis and returning Martyropolis to his Byzantine allies . Early in 591 , an army sent by Bahram was defeated by Khosrau ' s supporters near Nisibis , and Ctesiphon was subsequently taken for Khosrau by Mahbodh . Having restored Dara to Byzantine control , Khosrau and the " magister militum " of the East Narses led a combined army of Byzantine and Persian troops from Mesopotamia into Azerbaijan to confront Bahram , while a second Byzantine army under the " magister militum " of Armenia John Mystacon staged a pincer movement from the north . At the Battle of Blarathon near Ganzak they decisively defeated Bahram , restoring Khosrau II to power and bringing the war to an end . Aftermath . Having played a vital role in restoring Khosrau II to the throne , the Byzantines were left in a dominant position in their relations with Persia . Khosrau not only returned Dara and Martyropolis in exchange for Maurice ' s assistance , but also agreed to a new partition of the Caucasus by which the Sassanids handed over to the Byzantines many cities , including Tigranokert , Manzikert , Baguana , Valarsakert , Bagaran , Vardkesavan , Yerevan , Ani , Kars , and Zarisat . Most of the Kingdom of Iberia , including the cities of Ardahan , Lori , Dmanisi , Lomsia , Mtskheta , and Tontio became Byzantine dependencies . Also , the city of Cytaea was given to Lazica , also a Byzantine dependency . Thus the extent of effective Byzantine control in the Caucasus reached its zenith historically . Also , unlike previous truces and peace treaties , which had usually involved the Byzantines making monetary payments either for peace , for the return of occupied territories , or as a contribution towards the defence of the Caucasus passes , no such payments were included on this occasion , marking a major shift in the balance of power . Emperor Maurice was even in a position to overcome his predecessor ' s omissions in the Balkans by extensive campaigns . However , this situation was soon dramatically overturned , as the alliance between Maurice and Khosrau helped trigger a new war only eleven years later , with catastrophic results for both empires .