Justinian's successor was his nephew Justin II, who ruled from 565-574, becoming progressively insane. He started his reign by refusing subsidies to the Avars. This was Turco-Mongol tribal confederacy (khanate), which swept from southern Russia to Bohemia and the Balkans. Westward expansion had been stopped in Thuringia by Meorvingian Sigibert, but they then moved to the Hungarian plains, destroying the Eastern Roman-allied Gepids by 564-6. When the Lombards went west in 565, they settled farther south in Hungary, using it as a base to organize raids with Slavs to Byzantine areas. Emperors had bought them off, but Justin II refused. The Avar reaction was a decisive thrust into Dalmatia, where they destroyed or plundered all in their path. In 571, Justin sought a truce, whereby he paid 80,000 pieces of silver, much more than the original subsidy. This Avar threat emerged during the same years as the Lombard descent upon Italy, so Byzantine forces could do nothing to stop it. Also in 571, Christian Armenia had rebelled against Sassanian rule, and requested Byzantine protection as a Christian power. Justin agreed, even stopping tribute payments to Shah Chrosroes. War ensued in the East. Persians took the important bishopric of Dara on the Tigris with more than 250,000 captives. Justin went rapidly insane, openly persecuting Monophysites. His wife Sophia was able to buy a year's cease-fire in the East, and got her husband to raise the Palace Guard general Tiberius as her co-regent.
Tiberius became Emperor in 578. The situation was dire. In 575-7, Turks had appeared for the first time as Byzantine enemies, taking a fortress in the Crimea. More pressing were the Avars and their Slav raiders. Though Tiberius tried to hold them back with payments, from 577, they had begun to infiltrate in large numbers into Thrace and Illyricum, actually over bridges that Greek engineers had built as part of the subsidies. In 580, the Avars laid siege to Sirmium on the Sava river near Belgrade, which fell in 582. In that same year a Cappadocian officer named Maurice succeeded to the throne when Tiberius died of poison. He tried to follow the policy of his predecessors--paying off the Avars and fighting the Persians. The Avars continued to raid, occupying more of the Upper Balkans. Money to fight in the East was also lacking.
Byzantium was blessed temporarily in 590. When Chosroes of Persia died in 579, he was succeeded by the shah Hormisdas. A coup took his life eleven years later, and his son Chosroes II fled to Greek territory. Maurice granted his request for aid, which Chosroes used to gain power. The latter had promised Maurice a peace treaty along with restoration to Byzantium of Armenia and eastern Mesopotamia. Miraculously, Chosroes II kept his promise until 603, when Maurice was deposed. For the remainder of his rule, the Emperor focused on three issues. 1) He organized what was left of Justinian's acquisitions. In North Africa at Carthage, and Italy at Ravenna, he established exarchates as Imperial command posts. Totally military in nature, an exarch ruled them with absolute control over both military and civil matters. This was a new consolidation of power, and was effective as long as forces were available. 2) From the 590s on the Emperor sent repeated expeditions against the Avars in the Danube region and beyond. None were decisive given lack of troop discipline. 3) Maurice tried to be as frugal as possible. He reduced military rations, and declined to ransom prisoners of the Avars. This ultimately led to his downfall; when he ordered the army to stay in the Balkans for the winter, they mutinied, and in the tangle of imperial aspirants, a certain general Phocas became ruler, massacring Maurice's family.
Phocas' rule was a disaster. Several senators, provincial governors, and generals did not recognize him; "his eight-year reign brought the Empire to the nadir of its fortunes." It began with Chosroes II invading Byzantine lands as Maurice's avenger. By 607 they had taken western Mesopotamia, Syria, Armenia as well as central Asia Minor. By 608 they had streamed as far west as Chalcedon, within sight of Constantinople. During the same years, Avar-Slav incursions increased, with few troops available to stop them. Phocas' response was a campaign to forcibly convert the Empire's Jews. Many of them lived in areas threatened by Persians; their natural response was to welcome Persian conquest. In Antioch persecuted Jews went to so far as to turn on the Christians, massacring them, triggering a total flight from the city. Soon, Blues and Greens rampaged in the capital.
Byzantium was saved from Phocas by the military governor system Maurice had established. The exarch of Carthage and his second-in-command brother were too old to claim power, but they prepared an army and fleet under their sons. The army proceeded to capture Alexandria in 609, moving on towards the capital. The fleet under Heraclius went to Thessaloniki, where it augmented its numbers, leaving for Constantinople in 610. On 5 October, Heraclius was welcomed as emperor by a population disgusted with the past decade of turmoil.
Heraclius is early Byzantium's tragic hero, and his reign can be divided into two parts, the first lasting until 628. He was occupied incessantly with the Persians and Avars. Until 620, the situation appeared hopeless. The Avars were disbursed throughout the Balkans, where their Slav partners began to remain during the winters. From the East, the Persians made repeated advances. The Persian general Shahr-Baraz took Antioch and Damascus in 613, moving to Jerusalem by 614, plundering it, destroying the Church of the Holy Sepulchre, and carrying off the True Cross. Having Occupied Armenia already, in 619, Persians extended as far as Egypt, cutting off food supplies to Constantinople, causing famine and disease in Byzantium, which was now reduced to the capital and small parts of Asia Minor and the lower Balkans. By 620, Heraclius was preparing to flee to Carthage, when the Patriarch Sergius implored him to stay, telling him that the entire people would support him, and the Church would open its coffers to him. In the next two years, Heraclius reorganized Western Anatolia. Divided into four Themes, each region was provided with a strategos, an all-powerful military ruler on the exarch model. In these themes, army-age males were settled on inalienable grants of land held in return for military service. These Theme Armies were further provisioned by taxation, forced loans, and church contributions.
By 622, Heraclius was ready to campaign. He led his forces in person, the first ruler to do so since the 390s. He led the army behind the Persians to Armenia, causing Shahr-Baraz to withdraw from Asia Minor, after which the Persians suffered their first defeat. Heraclius returned to Constantinople to make a truce with the Avars, leaving his army in the field, which did not mutiny. In 623 he returned to the offensive, going through Armenia and Azerbaijan to burn the Shah's castle at Ganzak. Leaving a trail of destroyed Sassanian outposts, he almost made it to their capital Ctesiphon before winter. In 625, he moved past Ararat to capture Martyropolis and Amida. In southeastern Anatolia, the two armies met in frontal battle. Though Shahr-Baraz ambushed Byzantine forces inflicting heavy loss, Heraclius' personal courage and advances spurred his reserves to defeat the Persians again. The odyssey continued, however, when Chosroes II ordered a huge conscription and had his army march west, to implement an attack on Constantinople in alliance with the Avars. Heraclius did not come west, but remained to ravage Persian Azerbaijan with new Khazar allies. He left the defense to Sergius and his generals. The Persians got all the way to Nicomedia, and began sending small harassing flotillas to the capital, while the Avars laid active siege to the western walls. Though only possessing a small cavalry garrison of 12,000, Constantinople was ably defended by the walls and its populace, themselves encouraged by Sergius' daily processions with an icon of Mary. When in the first dew days of August Greek vessels destroyed flotillas of Persian and then Avar craft, the two allies panicked, and struck their camps. This marks the beginning of Avar decline. As for the Sassanians, Heraclius renewed the offensive in early 627, marching on the Shah's palace at Dastagird near Ctesiphon. Razates, the new Sassanian commander, avoided battle as long as he could. When they did meet near Nineveh, a daylong battle resulted in Greek victory. Dastagird was burned. Humiliated, Chosroes was murdered by his son Kava Siroe. The new Shah surrendered unconditionally, returning all conquered lands and captives, together with an indemnity and the True Cross. Heraclius entered Constantinople with the Cross in September 628, to the triumphal acclamation of his people, secure in the knowledge that Persia would never re-emerge as a threat.
After an interlude of six peaceful years when Byzantium appeared restored, Heraclius endured a disastrous epilogue to his rule from 634-38. In 622, the Arabian Muhammad had begun to preach Islam. By his death in 632, his new religion had gained a foothold in Arabia. In 634, as an extension of his successors' efforts to prevent decomposition of what was really a new super-tribe, Arab Muslim forces expanded into Byzantine Syria. A small Byzantine garrison was destroyed, and Heraclius, in Palestine to return the True Cross to Jerusalem, gathered an army of 80,000 men to meet the new threat near Antioch. The Muslim forces then fell back, awed by numbers, and the two armies met again on the Yarmuk river south of the Galilee in August. When a sandstorm emerged from the south and disoriented the Byzantines, the Muslim general Khalid charged. Byzantines gave way, and were massacred. By 637, Jerusalem had surrendered along with all of Syria, while Muslim armies were moving into Iraq and Egypt. Sickened physically and emotionally, Heraclius retired in 638, dying three years later.
As a footnote, Heraclius too was unable to escape theological problems with the West. In 634, his Patriarch Sergius had articulated a new formula to please Monophysites and Orthodox. It was that while Christ had two natures, they possessed a single motive force, or energy. It was still controversial. In particular, the monk Sophronius condemned it, and when he became Patriarch of Jerusalem, his opposition may have eased Muslim entry. Finally, in 638 Sergius made another pronouncement, again under Heraclius' orders. Monotheletism, it was that Christ was of two natures, and did not have a single energy, but possessed a single will. All Eastern Patriarchs agreed, but now the Western Pope John IV condemned it in 641, shortly after Arab armies arrived in Alexandria Egypt.
The century from 550-650 in the East could be called the 'hundred years disaster', 'the fall of the Dark Ages curtain', or, most charitably, the transition from Eastern Rome to the Byzantine Empire. Symbolic of this, by Heralius' death, the language of law, administration, and government was Greek, which had already become the language of art and intellectualism. Beyond this, though, the essential components of the Byzantine system were in place: separation from the West; Barbarians raids and settlement south of the Danube, even in states; and Islam as an ever-present threat in the Middle East and Anatolia. Out of this crucible emerged a state and society with a new political glue.
Mentioned earlier was the third wave of Barbarian invasions, consisting of Avars and Slavs. In terms of demographic and ecological effects, their impact is similar to that of the Lombards in Italy, such that they should be considered part of the same grouping. By the time of Phocas, there was large-scale Slav settlement beneath the Danube, as far south as Moesia and Thrace in Central Greece. It was a demographic and cultural disaster for the region. During the Slavic settlement, Greeks became frantic, large numbers of them fleeing for the coast. The great majority of old towns and settlements ceased to exist, with traditional Roman culture all but disappearing. Like Italy, the terrace system decayed as well, opening the way for youngerfill erosion and the contraction of agricultural yields. By the 610s, Byzantine possessions here had been reduced to coastal strips, and just like in Lombard Italy, the Dark Ages of irreversible natural and human decline had set in. As well, a slavicization of Byzantium would allow later Bulgar encroachment to proceed more thoroughly
We should, then, locate the onset of the general European Dark Ages from the 550-650 period. It is not entirely clear what set off this third wave of Barbarians, why the plague emerged with such consequences, why settled society proved so non-resilient, and why during the same years, Arab Bedouin proved unwilling to remain in the Arabian peninsula. Aside from fortuitous conjuncture, satisfactory explanations are elusive. One that has been offered lately to explain European, Asian, and even Meso-American changes during these century is a climatic mega-event somewhere in central Asia. An earthquake followed by a series of volcanoes spurred frantic migrations of all sorts of tribes, Avars included, into more settled areas. Also on the move was the plague. More settled areas, in turn, witnessed worsening agricultural conditions and poorer weather, perhaps set off by the seismic event. In Arabia, the event's impact on international trade was reflected in comparative impoverishment of local trade oligarchies as well as a growing gap between rich and poor both within clans and between tribes. It also made booty-oriented beduin restless, so that many would be more receptive to Muhammad's message of social justice and political expansion. Until geological historians do more research, however, this must remain conjecture.
Beyond a more Grecophile culture and language, what made Heraclius' state Byzantine upon his death? A) Geographically, the loss of the West, as well as Egypt (and soon North Africa), Arabia, Palestine, Syria, Mesopotamia--all historically Roman lands--gave Byzantium the territorial parameters it was to maintain more or less for the next 800 years. The demographic basis of the Empire now became the lower Balkans, Greece, and Western as well as at times Central Anatolia. B) The geopolitical rhythm from here on consisted of yearly campaigns to fend off Muslim offensives and Barbarian plundering/occupation in the Danube region. Twice--in 687 and 717--this took the form of Arab Muslim sieges of the capital, but in the East, it was mostly confined to yearly Muslim thrusts as far as Nicaea, halted only during times of internal unrest in the Islamic state. In the west, Barbarian hordes would often lay siege to cities, causing loss of life and an eventual sacking. Often, Avars or Bulgars could be bought off with tribute. C) The way that Byzantine leaders began to meet the threat was characteristic of the new state. Perhaps even from the time of Heraclius, the Themes, and their peasant armies, provided closer military control of threatened districts, as well as vast pools of mobilizable soldiers, in addition to agricultural surpluses. While Theme armies would at times revolt under strategos, they could effectively deny long-term Anatolian conquests to the Arabs (and later Turks), providing the basis for a tenth- century partial Byzantine reassertion.
D) Finally, an enduring, identifying characteristic of Byzantine society came to the fore as early as the Persian wars of Heraclius. During this conflict, the entire people had united behind him, taking the Patriarch Sergius' cue, who had opened the coffers of the church to him. Miraculously, Heraclius was able to leave Constantinople to defend itself in 626, and the people did not revolt, proclaiming an anti-emperor. Further, during the course of the war, the population in the thoroughly Christianized Greek and Armenian regions began to identify the religion with the state's survival. Thus, Christian conviction motivated a Byzantine quasi-patriotism. Though not causing it, Heraclius recognized it and made good, earnest use of it. The campaigns against the Persians became proto-crusades, and the religious element provided a previously unseen political cohesion. This cohesion would only grow when Byzantium was challenged by an opponent whose sole basis of identity, and legitimacy of conquest, was based on religion: Islam. Thus, by the middle of the seventh century, Byzantium had crystallized as a state and society socially and ideologically mobilized for war and defensive retrenchment.