The other uncontroversial story of the Byzantine economy is that of the Latin take-over of the Mediterranean. Latin sailors, traders and travellers came from the west to Byzantium throughout the period and Michael McCormick’s recent collection of data on eighth- and ninth-century Mediterranean travellers would suggest that even in the ‘dark age’ they did so in significant numbers.29 But by the mid-twelfth century it is clear that the Latin presence was on a new scale and a large proportion of Byzantium’s internal and external trade was in Italian hands. A crucial factor in this take-over were the treaties made by Alexios I Komnenos and his successors with first the Venetians, then the Genoese and Pisans, offering commercial privileges in exchange for military support. The terms varied, but essentially those so favoured gained a 10 per cent reduction in costs against their competitors, including of course their indigenous Byzantine competitors. No wonder that by the second half of the century the provisioning trade of Constantinople was largely in Italian hands and with it much of the carrying-trade of the Aegean.30 Halmyros, on the Aegean coast in central Greece, is not even mentioned before 1108, but thereafter the fact that Venetian, Pisan and Genoese merchants had made it their base for buying Thessaly’s agricultural produce, above all grain, ensured its rapid growth at the expense of older regional centres.31 Further south, Thebes tells a similar story. By the mid-1140s this hitherto unremarkable provincial town had become a major centre for the production of high-quality silk cloth, so much so that in 1147 it was sacked by the forces of Roger II of Sicily (1130–54) and its expert silk-workers taken as booty. Despite this, the town soon recovered and by 1162, when the Jewish traveller Benjamin of Tudela was there, its silk industry seems to have been thriving as ever.On one level the prosperity of middle Byzantine Thebes is just another example of what was described above: a prosperity which reached out into the provinces; but it is clearly more than that. The silk industry was a particularly high-value business that needed a stable market of wealthy consumers. Provincial aristocrats and clergy no doubt wore silk, but the chief centre of consumption in the Byzantine world was inevitably Constantinople. The rise of this particular industry in Thebes, some 600 kilometres from the imperial city, therefore suggests its chief market was not Constantinople, but the west.32 The rise of the Latins certainly does not mean that there were no Byzantine merchants; but by the end of the twelfth century, the Italians had taken a commanding position in the Byzantine economy. The rulers of Genoa, Pisa, and above all Venice, drew large profits from the eastern trade. Many of them spent much of their lives in Byzantine territory, either in the privileged Italian enclaves along the Golden Horn in Constantinople, or in places like Halmyros or Thebes. They built family houses and churches, where they buried their relations.33 Like the British East India Company in the eighteenth century, they had not come to conquer, but by the end of the twelfth century they had too much invested to leave its management in wayward local hands.