After the calamity of the Islamic Invasions, what were the consequences? We know now, that the Mediterranean world would never be the same again, but at that time, and for centuries afterwards, people sustained the hope that what had befallen them could be reversed.  Here we see in some detail the practical consequences of the loss of the core lands of the eastern Mediterranean. The Roman Empire, now enormously shrunken, managed to adapt and to hold its Nemesis at bay, for many further centuries. But economic, social and cultural decline were the inevitable results of such drastic surgery. That calamity affected the Roman Empire as much as it did the less developed and less urbanized Occident. If we can speak of a ‘Dark Age’, then this is when it began. The positive response in the Occident was as remarkable as the resistance and adaptation were in the East. A Frankish-Papal condominium emerged, uniting northern Italy - not with Constantinople - but with the now great kingdom of the Franks. Under the wing of the Carolingian kings, Christianity thrust its way into central Germania, a pagan and tribal heartland. The Franks thus initiated the expansion of Christendom eastwards, across the continent of Europe. Charlemagne marked the height of this process, forging a political and military coherence, as well as an economic, social and cultural revivification of the whole Occident, thereby laying the foundations for the European Middle Ages.