The Hanseatic League of cities in northern Europe arose from the merchants‘ association. It met for the first Hanseatic day in 1356 in order also to manage the political interests of the merchants.
The pirate Klaus Störtebeker was alternatively both ally and opponent.
The Stralsund peace in 1371 was a highlight of the joint undertakings. The name not only referred to a peace agreement after a war but rather an agreement in which 31 Hanseatic cities were involved and with which the Danish king Waldemar IV. was conquered.