The period from the beginning of the seventh century to the middle of the ninth was decisive for the history of the Byzantine empire. At the beginning of the seventh century, the idea of the Roman, or Byzantine, empire as the political configuration of the Mediterranean world - something that the Emperor Justinian had done his best to restore - still seemed valid, though there were already significant cracks in the edifice. By the end of the seventh century - let alone the middle of the ninth - that was a dream, though a dream to which the Byzantines obstinately clung. For the early years of the seventh century had seen the temporary Persian conquest of the eastern provinces of the Byzantine empire, soon followed by the Arab conquest which the Byzantines were to prove unable to overturn. The impact on the Byzantine empire of these events and the infiltration into the Balkan peninsula by the Slavs, was profound - politically, economically, culturally, and theologically. But the story of this impact is generally presented, both in the sources and in scholarly accounts, from the point of view of the centre, the Queen City, Constantinople. Central to the Byzantine world view, as it emerged with renewed confidence in the middle of the ninth century, was the idea of the empire, and the Emperor, as the guardian of Christian Orthodoxy, which was symbolized in the proclamation of the ‘Triumph of Orthodoxy’ with the final overthrow of iconoclasm in 843, a proclamation that became part of the normal ecclesiastical calendar, celebrated thereafter each year on the first Sunday of Lent. But that Orthodoxy, in its final form, had not been nurtured in Constantinople, nor had the wealth of liturgical poetry that came to celebrate it. Constantinople had reacted to the catastrophe of the early seventh century by plunging into heresy: first, the Christological heresy of monenergism, with its refinement, monothelitism, and then the heresy of iconoclasm, also believed - by both iconoclasts and their opponents - to be ultimately a matter of Christology. The Orthodoxy whose triumph was celebrated from 843 onwards had been defined, and celebrated, in Palestine, the province that had been lost for good to the Byzantines in the 630s. Orthodoxy, in fact, achieved its final definition at the periphery - and defeated periphery at that - and from there took over the centre. In this paper, we are not concerned with Christians who visited the Holy Land as pilgrims, but rather with those who belonged there: mainly monks, both natives and those who came to the Holy Land to live in the complex of monasteries in and around Jerusalem. How and why did these Palestinian monks come to play this role in the wider history of the Christian œcumene?