The Hanseatic League (German: die Hanse) was an alliance of cities, mostly de facto independent city states in central and northern Europe, in the medieval and early modern era. Most of those cities are situated at or close to the Baltic Sea, but trade contacts were also established to the North Sea and far inland.
The Hanseatic League originated in the High Middle Ages as an association of low German merchants who lived, worked and traded in several cities mostly along the Baltic Coast. By the Late Middle Ages the cities themselves had taken over the administration of the Hanse and it can be said that cities were "members of the Hanse" during that time. However, distinguishing between a league of people as opposed to a league of cities is difficult, as during the heyday of the Hanse all cities were dominated by the proto-bourgeois merchant elite (the German word Hanseat referring originally to a member of this class originates in that era). The Hanse amassed immense wealth, eliminated piracy in the Baltic and brought major developments to sailing (such as the cog, the dominant boat of the era) and trade in almost all of central Europe, as the hanseatic trade-network reached as far south as Nuremberg and as far east as Russia. With the rise of the Italian merchant republics and at the latest with the (re-)"discovery" of the Americas of 1492 the days of the Hanse were numbered as the major trade routes shifted south and west. While the Hanse was never formally dissolved, historians agree that some time in the second half of the 17th century the tradition of the Hanse finally came to an end after centuries of decline, and proto-nation-states, especially Sweden, Denmark, and Poland, came to control Baltic Sea commerce. Some former members of the Hanse, however did incredibly well for themselves even after that and many retained a degree of political autonomy to this day, most notable among these is the Freie und Hansestadt Hamburg. The wealth of that era can still be seen in the old towns of several former members of the Hanse and many cities (especially in Germany) still maintain their (former) Hanseatic status in their official long form names.