Any boundary drawn across conditions of flux is arbitrary, and several chapters in Part II delve back into seventh-century events, as background to the problems facing emperors once warfare on their eastern approaches became unremitting. Armies had to be stationed across the Anatolian plateau, combat-ready yet potentially self-sufficient, and emperors needed to forestall defections to the Arabs by those forces’ commanders. The balance between maintaining military effectiveness and ensuring trustworthiness already coloured Byzantine political thinking and strategy in Justinian’s era. But the problem gained a new edge from the Arabs’ ongoing challenge and, asWalter Kaegi shows, emperors were very fortunate that comparable tensions dogged the Muslim leadership and stymied its capacity for major invasions (see below, pp. 365, 373, 375, 392). By around 700 the Muslims were tightening their hegemony over Armenia after a brief revival of imperial influence there (see below, pp. 345–6). And in 705, Justinian II (685–95, 705–11) forcibly regained his inherited throne in Constantinople, aided not by a ‘Roman’ army, but by the Bulgars, now installed in the former province of Moesia. The emperor’s special relationship with barbarians as an alternative to his own forces would become a hallmark of the medieval empire. The deep-seated state of emergency is set out in detail by Marie-France Auz´epy, who shows how Leo III (717–41) and Constantine V (741–75) recast the formula for state survival set out by the first Justinian. Through reforming the army and identifying it very closely with their own regime, the Isaurian emperors allayed risks of a coup d’´etat and provided a strong right arm for state power, even while recognising the limits of the material defences affordable for Romans living in the provinces. They also provided the wherewithal, in the form of lower-denomination silver coins, for greater recourse to taxes raised in money (see below, p. 270). The sweeping powers of the autokrat¯or and his agents were tempered by concern for justice, providing a vent for the aggrieved through the channel of the emperor’s courts, but also ruthless punishment for proven malefaction (see below, pp. 275–7). The spiritual welfare of the emperors’ subjects was also catered for systematically, with numerous new sees founded. Furthermore, the ‘idols’ deemed to have incurred God’s wrath – and consequent disasters for the empire – were denounced and, eventually, destroyed. Thus iconoclasm is fitted by Auz´epy within a broader context of crisis, and her chapter as a whole illustrates the imperial order’s capacity for renewal. The fruits of this renewal ripened in the decades following the rulers’ final abandonment of iconoclasm in 843, while the Abbasid caliphs no longer led or funded massive incursions into AsiaMinor. The need to purge contaminating idols had lost its urgency, while devotion to images for accessing the divine was fervent in some quarters of the church. Shaun Tougher’s chapter demonstrates the standing of churchmen after the restoration of icon-veneration. Patriarchs could still be unseated from their thrones, like Photios (858–67, 877–86) in 867 (see below, p. 301). But churchmen and monks had stood up for icons, some earning the status of ‘confessors’, persons who had suffered persecution for true belief, albeit not death.One such churchman was Theophanes Confessor, the author of a chronicle that is one of our main sources for eighth- and early ninth-century Byzantine history. Commemoration of the restoration of icons to favour was celebrated annually at the Feast of orthodoxy (see below, p. 290). The gradual expansion in the material and demographic resources available to the emperors from the mid-ninth century onwards was therefore tempered by the esprit de corps and general repute of churchmen as orthodoxy’s guardians. The limits of the emperor’s ‘space’ were symbolised in the routes he did, and did not, take on his way to the liturgy in St Sophia.28 It may be no accident that one of the earlier – and victorious – eastern expeditions launched by Basil I (867–86) was directed against dualists, the Paulicians, as if to demonstrate his orthodox credentials in the drive against heretics. Basil’s expeditions against the Muslims of Melitene and Tarsus were, however, less successful, and his parading of his piety and generalship was at least partly designed to camouflage humble origins and a blood-soaked throne (see below, pp. 294–6). Equally, Byzantine defence installations could do little to curb the depredations ofMuslim raiders who had the nearby island of Crete as a safe haven and potential emporium for slave trading from the 820s on (see below, pp. 499–500). Yet their ability to sustain themselves through raiding implies fairly rich pickings to be had. This accords with other hints of economic vitality, for example the code for officials supervising trading and craft activities in the capital – the Book of the eparch, issued or reissued under Leo VI (886–912).29 Nonetheless, Byzantium’s armed forces were fully stretched in containing Muslim land raids. And the Christianisation of the Bulgars in the Balkans from c. 865 onwards rendered their polity more cohesive and militarily formidable than ever, even if their receipt of baptism from Byzantine priests made them nominally ‘spiritual sons’ of the Byzantines, and notionally deferential.30 With valuables and manpower leeching away to Muslim land raiders and pirates, Byzantium was hard put as ever to conduct large-scale campaigns on two fronts at once (see below, pp. 498– 500). Even after the death of Symeon of Bulgaria in 927 eased Byzantine concerns about its western neighbour, offensives to the east were limited in scale and largely confined to removing thorns from the flesh. A kind of equilibrium prevailed, compounded by the emperors’ reluctance to entrust their generals with armies of full-time soldiers schooled in aggressive warfare. Such an army could easily be turned against an emperor and this was, in effect, what happened after the rampages of the amir of Aleppo, Saif al- Dawla, became insufferable. Within a few years of the codification of the status of theme-soldiers’ military holdings,31 the raising of more full-time soldiers and switching of tactics to full-scale offensives,Crete was regained – and its conqueror, Nikephoros II Phokas (963–9), was sitting on the imperial throne. There is little doubt that the army’s size increased markedly in the later tenth century.32 This reinforced the challenge which ambitious army commanders posed to the young emperors claiming the right to rule through birth in the purple, Basil II (976–1025) and Constantine VIII (1025–8). Basil eventually quelled the revolts of his generals and associated his regime with the army to an extent unparalleled since the iconoclast soldieremperors. The protracted resistance of the Bulgarians to his attempts to impose hegemony provided opportunities for the exercise of war leadership in person. While the epithet of ‘Bulgar-slayer’ was only applied to Basil much later,33 his Bulgarian wars enabled him to square the circle and maintain larger armed forces, spectacularly intimidating neighbours on all sides, without falling prey to rebellion (see below, fig. 37 on p. 523). And the continually mounting agrarian and commercial prosperity and population size of the enlarged empire was most probably sufficient to sustain this army. What is less clear is whether the empire’s customary methods of painstaking tax-collecting and transmuting of revenues into soldiers’ pay were well geared for the armies that Basil II amassed. Such negotiable fiscal transactions required very many officials, and a significant increase in their numbers is suggested by the profusion of their seals in this period. Moreover, Basil set a precedent as ‘happy warrior’ and expansionist, without providing a male heir: his successors had to cope with a certain legitimacy deficit as well as with broader issues of strategy, the role of the armed forces and finding means of paying for them. The vitality, wealth, yet vulnerability of eleventh-century Byzantium is brought out inMichael Angold’s chapter. Culturally the empire was a hive of creativity, from the visual arts to literature. The volume of law-cases concerning money, property and inheritance is registered in a textbook assembled from a senior judge’s rulings and opinions, the Peira (literally, ‘trial, experience’).34 And Constantine IX Monomachos’ (1042–55) institution of a law school at Constantinople represented an attempt to ensure welltrained jurists and administrators for state service in an era of widespread litigation (see below, pp. 598–9). Byzantium had not seen such a pitch of general material well-being and diversity of faiths and cultures beneath the imperial aegis since the seventh century. The analogy holds good in strategic terms, too. In the mid-eleventh century, as in the 630s, the emperor could justifiably believe that his foes were subjugated or reduced to virtual impotence (see below, pp. 227–8). Yet then, without much warning, emperors found themselves combating raiders on three fronts: although the Pechenegs were more or less absorbed into the Balkans, the Normans in the west and above all the Turks in the east were not so amenable. In default of an incontestably legitimate dynasty ruling in Constantinople, several generals fancied for themselves the role of imperial saviour, for which there was pressing need. Disagreements over strategy and uncertainty as to the nature or intentions of the enemy were compounded by rivalries between generals and within the now labyrinthine Constantinopolitan court establishment. That Byzantium lacked flexibility in its response to external challenges at a time of internal tensions and inflated bureaucracy is not so surprising. More striking is the alacrity with which Alexios I Komnenos (1081–1118) recovered from the strategic mistakes of his early years as emperor and learned from them. He proceeded to reorganise his army, abolish many court titles and effectively debase the coinage. The empire had, after all, lost control of much of Anatolia to the Turks and was correspondingly impoverished: in cutting his imperial coat to fit diminished cloth, Alexios was pragmatically responding to severely reduced circumstances. There were precedents from earlier reigns for such economies and recourse to ‘flat-management’ style, as there were for the simultaneous emphasis on piety and plain living that Alexios made a hallmark of his regime (see below, p. 618). The empire’s material losses made correct worship all the more important, and although the church was now vocally resistant to emperors’ tampering with doctrine, Alexios and his descendants still saw themselves as guardians of doctrine, shepherds of their subjects’ souls (see below, pp. 617– 18 and fig. 46). This was also the case with Manuel I Komnenos (1143–80). Manuel displayed prowess in astrology, jousting and war in equal measure.35 His virtual ‘cult of personality’ included placing Christ Emmanuel on his earliest coins, a visual pun on Manuel’s name, while the list of subjugated peoples associated with Manuel on an inscription in St Sophia evoked the titulature of Justinian’s era.36 In emphatically aligning his regime with doctrinal purity and regularity of worship, Manuel resembled Justinian. The blend of expansionist bravado and inspired opportunism with tacitly defensive measures and ad hoc fortification-work belonged to a great tradition (see below, pp. 637–9, 642–4, 684, 685). And the Komnenian empire’s reversion to a pattern of far-flung strongholds and outer and inner zones of imperial orthodox order in some respects evokes the state of emergency of the late seventh and eighth centuries (see below, pp. 261, 264, 653–4). In the twelfth century, too, the imperial presence could be concentrated in ‘hot-spots’, the more fertile lands and strategically important points, where protection and exactions were more intensive, in contrast to those districts, maritime or inland, that were left exposed to barbarian incursions or occupied by outsiders. Manuel Komnenos still had formidable armed forces37 and a navy at his disposal, and these could well have helped him and also his successors gain new vantage-points, tap the burgeoning commerce of the eastern Mediterranean and forge alliances (see below, pp. 638–9, 645). Two twelfth-century developments complicated matters. Firstly, the political stability and administrative workings of Byzantium were now entwined with the extended family of the Komnenoi, together with a number of related families (see below, pp. 657–8). Lands, fiscal privileges and senior military posts were gathered in their hands, and for all the resultant advantages of cost-cutting and political cohesiveness, the expectations of individuals and branches of the familywere high, mutually competitive, and proliferating. This lessened the flexibility that the imperial administration had traditionally shown in attuning tax assessments to a property’s current capability to pay them.38 The effect of extensive tax exemptions, piling tax burdens on those left unprotected by privileges of one sort or another, was neither healthy for state finances nor conducive to longer-term political stability. Secondly, the twelfth-century imperial authorities had to contend with western Europeans of a different stamp from those of the earlier middle ages. The westerners were themselves fragmented and many individuals were primarily concerned with trading opportunities or a career rising high in the basileus’ service. Yet the intimacy of some western venturers with the Komnenoi and their successors paved the way for displaced members of the imperial family or pretenders to seek aid from western potentates and from causes with agendas of their own. Alexios Angelos’ fateful bid in 1201–2 for help from western leaders, one of whom was his brother-inlaw, was from this perspective nothing out of the ordinary, but it triggered the capture of Constantinople by the Fourth Crusaders. Already in 1185 a kinsman of Manuel I Komnenos, together with a pretender claiming (falsely) to be Alexios II,Manuel’s son, had given KingWilliam II of Sicily (1166–89) a pretext for sending an expedition that easily took Thessaloniki and only failed to reach Constantinople through overconfidence.39 Around 1184 another authentic Komnenos, Isaac, had taken control of Cyprus and started issuing coins in his own name, and it was a western crusader, King Richard I of England (1189–99), not the Constantinopolitan emperor, who eventually dislodged him. Thus some of the empire’s choicest lands and fortified towns were proving to be highly vulnerable, or self-sufficient imperial entities, a foretaste of conditions after 1204, and indeed after the restoration of imperial status to Constantinople at the hands of Michael VIII Palaiologos (1258–82).