Justinian died childless on 14 November 565. The succession had been left open.One of his three nephews, called Justin, secured election by the senate and succeeded his uncle; he had long occupied the minor post of cura palatii but he was, perhaps more significantly, married to Sophia, one of Theodora’s nieces. The only serious contender was a second cousin of Justinian’s, also called Justin: one of the magistri militum, he was despatched to Alexandria and murdered, reportedly at the instigation of Sophia. Justin II (565–78) continued, or reinstated, Justinian’s policy of religious orthodoxy, though he – or at least his wife, Sophia – had earlier inclined towards monophysitism. In renewing his uncle’s religious policy, Justin restored religious harmony between east and west, and he affirmed this shared orthodoxy by a gift to the Frankish queen Radegund of a splendid enamelled crucifix containing a relic of the True Cross. This inspired the greatest Latin hymns in honour of the cross, Venantius Fortunatus’ Pange lingua and Vexilla regis. But at the same time Justin sought reconciliation with the monophysites. This attempt at reconciliation ended in 572, with the monophysites’ rejection of Justin’s so-called second Henotikon; this rejection resulted in th persecution of the monophysites which John of Ephesus recorded in his Church history.37 But Justin is remembered chiefly for his ill-advised foreign policy: by refusing to maintain alliances with barbarian tribes, not least the Avars, or to preserve peace with Persia, he gravely weakened the empire’s position. Throughout the century, the Romans had been concerned for the security of the Danube frontier. Both Anastasius and Justinian had invested a good deal in building a line of forts and fortifying cities close to the frontier. In addition to this, Justinian had established alliances with various of the barbarian groupings – the Antes around 545 and the Avars in 558 – and had used them to check other barbarian peoples north of the Danube. Another set of barbarians, which proved a constant concern, was the Slavs: by the middle of the sixth century they were established along the north bank of the Danube, from where they made raids across the river into Byzantine territory, and from around 560 they began to winter on Byzantine territory. Within a few days of Justin’s accession, an embassy arrived from the Avars, requesting the tribute they had been accustomed to receive from Justinian in return, they claimed, for not invading the empire and even for defending it against other barbarians. Justin haughtily rebuffed them, but since the Avars were more concerned with the Franks at this stage, Justin’s action provoked no immediate response. Two years later, Justin was able to benefit from war between the barbarians. When the Lombards and the Avars formed an alliance to crush the Gepids, another barbarian group who occupied Pannonia Secunda and held the city of Sirmium, he was able to seize Sirmium, and held on to it during the war with the Avars that followed. The fall of the Gepids had further consequences for the empire, as the Lombards, who were occupying the borders of Noricum, now had the Avars as immediate neighbours. To avoid this they headed south and invaded northern Italy, with which many of them were familiar, having served there as allies ofNarses in 552.38 Under their king, Alboin, the Lombards took most of Venetia in 568 and most of Liguria in the following year, including Milan; Pavia offered more resistance but it, too, fell in 572. Elsewhere barbarians made inroads. Moorish revolts in North Africa caused the death of a praetorian prefect in 569 and two magistri militum in the next couple of years. In Spain, the Visigoths attacked the Byzantines, taking Asidona in 571 and Cordoba in 572.39 It would therefore seem that 572 was not a propitious year in which to provoke the Persians. However, that was the year when Justin refused the first annual tribute under the fifty-year peace negotiated by Justinian, having evidently paid the three-year tribute due in 569. The Christians of Persian Armenia had risen in revolt against their governor’s (marzban) attempts to impose Zoroastrianism on them and appealed to Justin. Justin not only refused the tribute due in 572, but also threatened to invade Persia and depose Khusro if attempts to turn the Armenians from Christianity persisted. The Armenian revolt was successful, and they were joined by the Iberian kingdom. Justin ordered an invasion of Persia.His cousinMarcian, appointed magister militum per Orientem in 572, attacked Arzanene on the southern border of Persian Armenia, and the next year attacked Nisibis. The Persian response, once they had overcome their surprise at the Roman attack, was devastating: they invaded Syria and took Apamea, then relieved Nisibis before besieging and capturing the fortress of Dara. News of the fall of Dara drove Justin mad, and his consort Sophia took the reins of power. She negotiated a one-year truce with the Persians for which the Romans paid 45,000 solidi, half as much again as had been due; this was later extended to five years, at the old rate of 30,000 solidi a year. But as a woman, Sophia could not rule as regent herself, and in December 574 she persuaded Justin to promote Tiberius, the count of the excubitors, to the dignity of caesar. Although Justin lived on until 578, government was effectively in the hands of Sophia and Tiberius. Sophia is, in fact, a somewhat neglected Byzantine empress. Though far less famous than her aunt, unlike Theodora she played a direct role in Byzantine politics, securing the succession both of her husband and of Tiberius II (578–82), whomshe vainly hoped to make her second husband. She is the first empress to appear on Byzantine coins together with her husband.40 Theophanes the Confessor, who clearly disliked women with pretensions to power, paints an ugly picture of Sophia and her meddling in imperial matters, as he did of Irene, the first Byzantine empress to rule in her own name. It may be significant that he has comparatively little to say about Theodora. Tiberius became emperor in 578, but by then had already effectively been governing for four years. In many respects he was the opposite of his predecessor: whereas Justin was financially cautious to the point of being regarded as miserly, but militarily ambitious, Tiberius bought popularity by reducing taxes, but in military matters exercised caution.He also called a halt to the persecution of the monophysites, on which Justin had embarked. Tiberius quickly realised that the empire did not have the resources to engage with its enemies on all fronts. He thus secured the support of the Avars on the Danube frontier by paying them tribute of 80,000 solidi a year. This gained not just a respite from hostilities, but Avar support against the Slavs: with Byzantine backing, the Avar cavalry devastated the Slavs’ territories on the banks of the Danube. However, this truce with the Avars did not last long. In 580 they attacked Sirmium, and after a lengthy siege the city was ceded to the Avars in 582 under an agreement which allowed the garrison and population to withdraw to Roman territory in return for 240,000 solidi, the sum total of the tribute not paid since the Avar attack. During the siege of Sirmium many Slavs crossed the Danube and invaded Thrace, Macedonia and what is now Greece: they would eventually settle throughout the Balkans, although there is no evidence for Slav settlements (called Sklaviniai by the Byzantines) until the next century.41 The attempt to buy off the Avars and secure peace on theDanube frontier was to enable Tiberius to concentrate on the Persian frontier, where his aims seem likewise to have been modest: building up enough strength to re-establish the peace that had been broken by Justin. The one-year truce negotiated by Sophia needed to be extended, but the five-year truce that had later been negotiated seemed to Tiberius too long. On his accession as caesar this truce was set at three years, on the understanding that in the meantime envoys would seek to establish a more enduring peace. At the end of the extended truce, the Byzantine army in the east was in a position to make inroads on the Persians, and had occupied Arzanene; the army was led by Maurice, who had succeeded Tiberius as count of the excubitors on Tiberius’ elevation to caesar. Negotiations were underway for a peace that would restore the fortress of Dara to the Byzantines, but in the course of these negotiations – in 579 – Khusro died. His son Hormizd IV (579–90), who succeeded him, broke off negotiations, and war continued. In August 582 Tiberius himself died, having crowned Maurice augustus the previous day. Maurice (582–602) was an effective general, who had already achieved military success under Tiberius before becoming emperor himself. Even if he is not the author of the military treatise called the Strategikon, such an attribution is not inappropriate. The treatise certainly reflects late sixthcentury Byzantine military practice, with its stress on the importance of cavalry in warfare and provision for campaigning across theDanube.42 Like his predecessor, Maurice initially concentrated his military efforts on the Persian front, and sought to deal with the other threats to the empire by diplomacy and tribute. At the beginning of his reign he paid the Frankish king Childebert II (575–95) to attack the Lombards in northern Italy, which he did in 584, securing the submission of the Lombard dukes. This was repeated in 588 and 589. Maurice had less success on the Danube frontier. Two years after his accession, the Avars demanded an increase in their tribute from 80,000 to 100,000 solidi, and when Maurice refused, they seized Belgrade (then known as Singidunum) and attacked other cities in the surrounding region.Maurice had to pay the extra 20,000 solidi in order to recover Belgrade and secure peace. But theAvars soon allowed the Slavs to overrun and ravage Thrace; the Slavs reached Adrianople and the LongWall before they were driven back. After that, the Avars themselves crossed the Danube and made for Constantinople. Having easily defeated a Byzantine force of 10,000 sent against them, the Avars crossed theHaemus mountains, invaded Thrace and besieged Adrianople; they were only defeated in 586 by Droctulft, a Lombard duke, who came to the service of the empire. In the same year Thessalonica was besieged by the Slavs and was only saved, so its citizens believed, by the intervention of their patron saint Demetrius.43 On the Persian front the war dragged on inconclusively. There was a mutiny in the army when Maurice attempted to cut pay by a quarter, to alleviate the drain on the treasury, and Martyropolis, in Arzanene, was taken by the Persians in 590. Soon, however, there was a dramatic change of fortune. The Persian shah, Hormizd IV (579–90), was killed in a rebellion led by one of his satraps, Bahram.His son Khusro fled to the Byzantines and with their help in 591 crushed Bahram’s rebellion and secured the Persian throne. In return for the help of theByzantine emperor, Khusro II (590–628) gave up his claim to Armenia and Arzanene, and restoredMartyropolis and Dara to the empire (see below, pp. 169, 337). After twenty years, there was once again peace between the Byzantine and Persian empires.Maurice now turned his attention to the Danube frontier. In 592 the khagan of the Avars demanded an increase in the tribute paid him.With his troops transferred from the now quiet eastern front, Maurice responded by confronting the Avars, who were obliged to abandon their attempt to occupy Belgrade. This did not stop them from invading Thrace, but they left abruptly under the impression that their homeland in Pannonia was in danger.44 However, the real object ofMaurice’s military policy seems to have been the Slavs: in the interests both of preserving resources and of effective military strategy, Maurice ordered the Byzantine troops to engage with the Slavs in their settlements beyond the Danube. The army, accustomed to rest during winter, threatened to mutiny. The next year another measure was introduced, aimed at increasing efficiency and saving money: instead of receiving cash allowances for their military equipment, they were to be issued with it directly. This was deeply unpopular. The Avars made further attacks, being rebuffed in their attack on Belgrade and Dalmatia in 598, and failing to take Tomi on the west coast of the Black Sea in 599. Later they threatened Constantinople itself, but a bout of plague in the Avar camp led the khagan to withdraw and agree a treaty in which the Danube was recognised as the frontier. Maurice quickly revoked the treaty and in 600 the Byzantine army defeated the Avars. The next year was quiet, but in 602 the Byzantines made successful attacks on the Slavs north of the Danube. Maurice gave orders for a winter campaign in Slav territory. This time there was open mutiny: the commander of the army fled, and under a new commander called Phocas the troops advanced on Constantinople. Maurice, who had made himself unpopular with his economies, found himself defenceless in his capital. After a bungled attempt to seize his son’s father-in-law, Germanus – to whom the troops had offered the crown – Maurice found himself facing a popular riot and the palace of the praetorian prefect of the east was burned down. Maurice fled, and Phocas was proclaimed emperor on 23 November 602. A few days later Maurice was executed, after his sons had been slain before his eyes. The death ofMaurice and the accession of the usurper Phocas I (602–10) left the empire in a fragile state: civil war weakened the empire within, and external enemies took advantage of the weakness thus revealed. As the seventh century advanced matters looked very black indeed.