The dune strip, being dry because relatively high as well as sandy, attracted early settlers. Here the Romans fortified the outlet of the Rhine west of the present Leiden; here the modern residence of the sovereign and the government had its origin as the garden of a count, as the Dutch name, 's Gravenhage, indicates. The swamp itself, with its many lakes and peat areas, was less attractive. In some places small groups of people ventured to leave the uplands and settle in lowlands, building artificial mounds in order to raise their dwellings above high tides and storm waves. Groups of fishermen also settled along the shores of the inland basins and used the protected inland waters as fishing grounds. Such settlements grew in importance; seafaring as well as fishing became an important occupation; and in the Middle Ages many of the towns thus started became members of the Hanseatic League and traded along the coasts of the North Sea and the Baltic. But man cannot live on fish alone, and the problem of where to get the other necessary kinds of food always confronted the fishing settlements. This led to the discovery that the swamps and even the floors of the shallowest parts of the many lakes and of the inland marine basin contained fertile soils, which could be used for grazing and crops if surrounded by dikes and drained. The Dutch lowland still contains an intricate assortment of these reclaimed floors of former bodies of water surrounded by dikes and drainage canals, into which the surplus water is pumped.
The area reclaimed from the water was at one time an insignificant possession of the German Empire and later of Spain. For a long time it was completely eclipsed by the high culture of nearby Flanders on the south, but the same water which had been conquered with so much difficulty could be used to flood the land once more in case of need, and thus to stop invaders. Aided in this way the small group of individualists who had made their own land and fought for its freedom gradually gained power until for a short time they became the dominant nation of Europe. A decline soon followed, however, for Holland was too small to maintain the leadership in world politics. Nevertheless, much of the old spirit is still left and is responsible for Holland's present high cultural standing.