The Hanseatic League, a powerful confederation of merchant guilds and market towns in Northern Europe, emerged in the 13th century as a dominant commercial force, with Lubeck, its leading city, becoming a major hub for trade. The League facilitated commerce across the North and Baltic Seas, and its influence began to clash with Denmark's efforts to control these vital trade routes. The Danish monarchy sought to leverage tolls and tariffs from the passage through the Øresund Strait, a strategic choke point that connects the North Sea to the Baltic Sea, which was crucial for the League's trading interests.
Northern Europe in the 1400s, showing the extent of the Hanseatic League. @ Professor G. Droysens
During the reign of King Valdemar IV (r. 1340-1375), Denmark sought to expand its control over the Baltic region, attempting to exert influence over the Hanseatic cities. In response, the League defended its commercial interests, which led to escalating tensions. The League's network of alliances and their naval capabilities often allowed them to confront Denmark effectively, ensuring the protection of their trade routes.
One of the most significant conflicts between Denmark and the Hanseatic League was the Second Dano-Hanseatic War (1361-1370). The conflict began when Valdemar IV seized the city of Visby on the island of Gotland, an important trading center under the League's influence. This aggressive move prompted the League to form a military coalition, resulting in a decisive naval battle off Helsingborg in 1362. Despite initial setbacks, the League's superior naval power and alliances with other Baltic powers forced Denmark into a settlement.
The conflict culminated in the Treaty of Stralsund in 1370, which marked a major victory for the Hanseatic League. The treaty granted the League significant trading privileges in Denmark and effective control over the Danish towns of Helsingborg, Malmo, and Falsterbo. It also ensured that the League could influence Danish succession, effectively limiting Denmark's power in the region and solidifying the League's dominance in Baltic trade. For several years, the Hanseatic League controlled the fortresses on the Sound, the strait between Skåne and Zealand.