By the sixth century, the unity of the Mediterranean had been shattered; it was no longer mare nostrum, either politically or commercially. There have been attempts to show that the fundamental unity of the Mediterranean as a trading space, at least, survived until the Islamic conquests of the seventh century (culminating in the invasion of Spain in 711), or even until the Frankish empire of the incestuous mass-murderer Charlemagne acquired control of Italy and Catalonia. There have also been attempts to show that recovery began much earlier than past generations of historians had assumed, and was well under way in the tenth or even the ninth century. It would be hard to dispute this in the case of the Byzantine East, which had already shown some resilience, or in the case of the Islamic lands that by then stretched from Syria and Egypt to Spain and Portugal, but the West is more of a puzzle. It is hardly an exaggeration to say that some historians observe decline at the same moments as others detect expansion. To this one can sensibly answer that there was enormous regional variation; but the question remains when and whether the Mediterranean lost, and then recovered, its unity. Just as in antiquity the integration of the Mediterranean into a single trading area, and subsequently into a single political area, had taken many centuries, from the Dark Age of the tenth century BC to the emergence of the Roman Empire, so in the era of the ‘Third Mediterranean’ the process of integration was painfully slow. Full political integration was never again achieved, despite the best efforts of invading Arabs and, much later, Turks. The loss by Byzantium of so many of its mainland possessions to the Slavs and other foes did leave the empire with several remarkable assets. Sicily, parts of southern Italy, Cyprus and the Aegean islands remained under Byzantine rule, and the empire drew wealth from gold and silver mines in several of these lands. Even Sardinia and Majorca were under Byzantine suzerainty, but it is unclear whether a functioning network of communication across the Mediterranean still existed.