Contemporary urbanization patterns around the North Sea can only be understood by looking at their long-term development and studying how these patterns arose and evolved over the centuries. If we look no further back than the Industrial Revolution, we get a distorted picture. The fact is that urbanization patterns were for the most part already established before that period, as can be clearly seen in the composite map showing all the cities and all reference years.
 Major port cities like Hamburg, Amsterdam, Rotterdam and Antwerp emerged during the late Middle Ages. Many other cities of importance today also date back to that period. The Industrial Revolution was decisive for only two groups of cities: those in the English Midlands and in Germany’s Ruhr area.
 The maps reflecting the situation in 1300 and 2015 reveal that the type of landscape had a huge impact on the urbanization patterns. Landscape provides continuity. In reaction to dramatic changes wrought by political and economic processes, the areas around the North Sea behaved like communicating vessels: the cities in the Southern Netherlands contracted, those in the Northern Netherlands expanded, Holland declined, England prospered.
 A succession of major economic and political processes is crucial to our understanding of the position, function and significance of today’s key North Sea cities. The foundations of urban patterns around the North Sea were established in the period before 1500. It is noteworthy that for centuries the epicentre of major port cities lay in the politically fragmented areas along the eastern shore of the North Sea here powerful and enterprising townsmen ensured an intensive exchange of goods.
 In the decades before and after 1600, the far-reaching political changes that occurred during the Dutch Revolt resulted in a shift in prosperity from the southern to the northern provinces, which subsequently experienced the Golden Age. While the southern provinces were constrained by their Spanish rulers, in the newly formed Republic where wealthy citizens were in charge, the cities of Holland flourished as transhipment and trading centres.
 During the eighteenth century, there were more dramatic shifts: the centre of gravity moved to the other side of the North Sea, to England, where the character of the economy was completely transformed by the Industrial Revolution and the main port cities were now part of a kingdom that evolved into the British Empire in which both government and entrepreneurs played an important role.
 Ever since industrialization took hold in northern France, Belgium and the Ruhr in the early nineteenth century, the North Sea region has been characterized by several economic epicentres that have managed to survive further far-reaching economic changes in the twentieth century. A consolidation of the pattern of cities around the North Sea occurred, seemingly due to the fact that, since the birth of the welfare state and the European Union, national governments have concentrated on the development of the economy, the population and the cities.