The urbanization did not take place at the same time in the individual parts of the Oldenburg monarchy. In Schleswig-Holstein and Denmark most towns date from the Middle Ages and very few were founded between 1500 and 1800. In the other parts of the monarchy these centuries were the main period of urbanization, in Norway above all, because of the timber industry. At the estuaries of rivers saw-mills were placed, and around them settlements emerged with a certain international trade because of the timber export. In due course these settlements obtained the formal status as towns.Until the middle or the end of the eighteenth century Northern Norway, the North Atlantic provinces (Iceland, Faroes, Greenland) and the Virgin Islands were governed by privileged trading companies. Only when the state took over the government, urbanization began. This is especially clear in Iceland and Northern Norway about 1790, but also in the Virgin Islands thirty years earlier.