The Hanseatic League
The powerful trading community known as the Hanseatic League was organised in the mid-13th century and its member towns quickly grew rich through the import and export of goods that included grain, ore, honey, textiles, timber and flax. The league was not a government as such, but it did defend its ships from attack and it entered into monopolistic trading agreements with other groups, such as the Swedes. It achieved its powerful trading position through bribery, boycotts and other underhand methods. The Hanseatic League members did work hard to prevent war among their partners, for the simple reason that conflict was bad for business.
Seven Dutch cities along the IJssel River were prosperous members: Hasselt, Zwolle, Kampen, Hattem, Deventer, Zutphen and Doesburg. It's ironic that the Hanseatic League's demise is mostly attributable to the Dutch. The traders of Amsterdam knew a good thing when they saw it and during the 15th century essentially beat the league at its own game, outmuscling it in market after market.