"Would all of Europe soon go the way of northern India? By 1529, with the Turks besieging Vienna, this must have appeared a distinct possibility to some. In actual fact, the line then stabilized in northern Hungary and the Holy Roman Empire was preserved; but thereafter the Turks presented a constant danger and exerted a military pressure which could never be fully ignored. Even as late as 1683, they were again besieging Vienna. Almost as alarming, in many ways, was the expansion of Ottoman naval power. Like Kublai Khan in China, the Turks had developed a navy only in order to reduce a seagirt enemy fortress—in this case, Constantinople, which Sultan Mehmet blockaded with large galleys and hundreds of smaller craft to assist the assault of 1453. Thereafter, formidable galley fleets were used in operations across the Black Sea, in the southward push toward Syria and Egypt, and in a whole series of clashes with Venice for control of the Aegean islands, Rhodes, Crete, and Cyprus. For some decades of the early sixteenth century Ottoman sea power was kept at arm’s length by Venetian, Genoese, and Habsburg fleets; but by midcentury, Muslim naval forces were active all the way along the North African coast, were raiding ports in Italy, Spain, and the Balearics, and finally managed to take Cyprus in 1570–1571, before being checked at the battle of Lepanto."