The island conquered by the Ottomans in 1669 after a long siege was Crete.
The conquest formed the climax of the Cretan War, fought mainly between the Ottoman Empire and the Republic of Venice from 1645 to 1669. Crete was strategically important because it occupied a central position in the eastern Mediterranean and served as Venice’s major base for controlling maritime routes.
Ottoman forces captured much of the island during the war, but Venice retained the heavily fortified city of Candia, now Heraklion, for more than two decades. The Siege of Candia became one of the longest and most destructive sieges in European history. In 1669, after prolonged bombardment, assaults, shortages, and negotiations, Venetian commander Francesco Morosini surrendered the city. The remaining Venetian forces evacuated, completing the Ottoman conquest of Crete.
The island remained under Ottoman rule for centuries, although parts of it experienced revolts and foreign intervention. Crete eventually gained autonomy and later united with Greece in the early twentieth century. The main mix-up is with Cyprus, which the Ottomans conquered from Venice in 1571, not 1669.