Lübeck and Hamburg formed an alliance in 1241, gaining control over most of the salt-fish trade and access to salt-trade routes from Lüneburg. In 1266, the Hansa was granted a charter for operations in England by Henry III. The Hanseatic League, or Die Hanse, took the place of Visby, the previous center of trade and it became the center of all the sea trade that linked the areas around the North Sea and the Baltic Sea and acted as a base for northern German merchants who spread east and north. Lübeck and Hamburg were joined by Köln in 1282.

The Hansa kept growing, and at the height of its power over sixty cities were directly represented in the association, each with its own merchant association and parliament to govern trade policies.

Its regional assemblies were known as “thirds”: The Rhennish third was based on the Rhine trade, the Wendish third on Baltic shipping out of Lübeck, and the Prussian third on the trade of grain from the lands of the Teutonic Order. Lübeck, being a free imperial city, had an advantage over most of the other cities politically, and geographically it also held a predominant position, with all Baltic trade in either direction going through its port. Key towns such as Danzig and Riga were soon established on the east Baltic coast under Lübeck law, which mandated that they had to obey the Lübeck city council in all legal matters. Other important cities which became members of the Hanse included Thorn, Elbing, Königsberg, and Krakow.

Hansa societies worked to acquire special trade privileges for their members and their network of alliances formed throughout the Holy Roman Empire grew to include around 170 cities. The league established significant additional Kontors, or trading centers, in present-day Belgium, Norway, Denmark and England, trading in timber, furs, resin, flax, honey, wheat and rye, copper, iron and herring. To be eligible to work at a Kontor, a merchant had to be married, of good repute and commit himself to a year’s term. In these Hansa cities along the trade routes, a distinct architecture formed, usually three storied structures with a store on ground level, a warehouse on the second floor and an office/ apartment on the top floor. German colonists under the Hanse’s supervision built many towns in the Baltic such as Reval, Riga, and Dorpat, and trained pilots and erected lighthouses.

To accommodate the larger loads they could now sell, the merchants developed the “Baltic cog,” a rugged, flat bottom, square rigged ship, and the merchants also formed partnerships to buy shares of a cargo so that if the load was lost due to sinking or pirates, the loss could be spread out and not be devastating to one party, and for protection and safety, the ships sailed in large convoys. At their height of its power in the late 1300s, the Hanseatic League wielded significant economic clout and their well-armed ships could even influence Imperial policy. The Hanse capital eventually moved to Danzig, the main port for traded merchandise along the Vistula river.

Changes in European economy, emerging territories, new forms of currency and different shipping practises all put the League in a weaker position as the Swedish Empire took control of much of the Baltic, Denmark regained control over its own trade, the Kontors in Novgorod and in Brugge were closed or defunct, and the authority of the German princes grew more powerful.

The League was sinking under the progress around it and its decline began, further eroded by the chaos of the Reformation, the new power of English and Dutch merchants and the effects of the Ottoman Turks on shipping routes. By the time of the last Hansa meeting in 1669, only nine members attended. Only Lübeck, Hamburg and Bremen remained as members until its final, formal demise in 1862.