The early history of Genoa was not unlike that of Venice; in so far at least, that, like it, Genoa had been for some centuries under the control, if not the vassal, of the eastern empire: at the period, however, to which we are now referring, the Genoese had a large colony at the seaport town of Heraclea, in Thrace. From this place the gratitude of the Greek emperor, Michael, recalled them, at the same time giving them the exclusive privilege of the suburb of Galata—a settlement whereby, more than by anything else, the commerce of the Byzantine empire was revived.[368] [Sidenote: Genoese settlement at Galata and Pera.] Though indulged in the use of their own laws and magistrates, the Genoese were required to submit to the duties of subjects, and undertook, in case of a defensive war, to supply the Greek emperor with fifty empty galleys and fifty more completely armed and equipped. In consideration of these services, and to afford them protection from the Venetian fleets, the Genoese were allowed the dangerous privilege of surrounding Galata with a strong wall and wet ditch, with lofty towers and engines of war on their ramparts. No wonder that, having secured so much, they should seek to acquire more, and that, within a short space of time, they had covered the adjacent hills with their villas and castles, each fort being connected with the next, and protected by new fortifications. Nor, as was natural, did they stop here; they soon sought to possess themselves of the whole trade of the Black Sea, long the especial patrimony of the emperors of Constantinople, and a prerogative which, in the reign of Michael, had been acknowledged by even Bibars, the Mamluk Sultan of Egypt. [Sidenote: Arrogance of the Genoese, who at last rebel, A.D. 1348,]