Up to the end of the Middle Ages the world was divided into a number of almost self-contained regions which only made contact through strictly limited channels of trade. It is indeed possible to maintain, as Fritz Rörig has done in a brilliant article, that the medieval world already enjoyed a world-economy, for the spice trade and the silk trade, the voyages of the Norsemen and the explorations of the Arabs, even the wanderings of occasional travellers and missionaries, gave external contacts of varying importance. Nevertheless western Europe, the Near East, India and Indonesia, the Far East, to mention only the great and obvious divisions, each followed its own particular way of life.

Then, from the end of the fifteenth century onwards, contacts were increased and became more and more active, slowly helping to produce a single market for the whole world. Faced with new tasks, the European peoples who bordered on the Atlantic developed and applied new economic techniques. They changed the framework of their economic organization, created new methods of co-operative action and new state departments and above all new merchant companies. They improved their techniques and their methods of using capital, changing their methods by a new organization of property and by a re-introduction of slavery. The states intervened more directly in economic affairs and slowly created modern colonies; their methods, in general terms, became accepted as Mercantilism and eventually developed into modern capitalism.