Also called Hansa, German Hanse, organization founded by north German towns and German merchant communities abroad to protect their mutual trading interests. The league dominated commercial activity in northern Europe from the 13th to the 15th century. (Hanse was a medieval German word for "guild," or "association," derived from a Gothic word for "troop," or "company.")
Northern German mastery of trade in the Baltic Sea was achieved with striking speed and completeness in the late 12th and early 13th centuries. After its capture by Henry the Lion in 1158, Lübeck became the main base for Westphalian and Saxon merchants expanding northward and eastward; Visby, on the Swedish island of Gotland, was soon established as a major transshipment centre for trade in the Baltic and with Novgorod, which was the chief mart for the Russian trade. From Visby, German merchants helped establish important towns on the east coast of the Baltic: Riga, Reval (now Tallinn), Danzig (now Gdansk), and Dorpat (now Tartu). Thus, by the early 13th century Germans had a near-monopoly of long-distance trade in the Baltic. In the meantime, merchants from Cologne (Köln) and other towns in the Rhineland had acquired trading privileges in Flanders and in England.
The decisive steps in the formation of the Hanseatic League took place in the second half of the 13th century. While overseas, the German merchants had tended increasingly to form associations ("hanses") with each other in order to secure common action against robbers and pirates. From the mid-13th century this cooperation became much more extensive and regularized, and by 1265 all the north German towns having the "law of Lübeck" had agreed on common legislation for the defense of merchants and their goods. In the 1270s a Lübeck-Hamburg association that had acquired trading privileges in Flanders and England united with its rival Rhenish counterpart, and in the 1280s this confederation of German merchants trading in the west was closely joined to the association trading in the Baltic, thus creating the Hanseatic League.
The Hanseatic League attempted to protect its ship convoys and caravans by quelling pirates and brigands, and it fostered safe navigation by building lighthouses and training pilots. Most importantly, it sought to organize and control trade throughout northern Europe by winning commercial privileges and monopolies and by establishing trading bases overseas. The league established permanent commercial enclaves (Kontore) in a number of foreign towns, notably Bruges in Flanders, Bergen in Norway, Novgorod in Russia, and the Steel Yard in London. The league's principal trade consisted of grain, timber, furs, tar, honey, and flax traded from Russia and Poland to Flanders and England, which in turn sent cloth and other manufactured goods eastward to the Slavs. Swedish copper and iron ore were traded westward, and herring caught off the southern tip of Sweden was traded throughout Germany southward to the Alps.
The Hanseatic League's aggressively protectionist trading practices often aroused opposition from foreign merchants. The league typically used gifts and loans to foreign political leaders to protect its commercial privileges, and when this proved inadequate, it threatened to withdraw its trade and occasionally became involved in embargoes and blockades. Only in extreme cases did the league engage in organized warfare, as in the 1360s, when it faced a serious challenge from the Danish king Valdemar IV, who was trying to master the southwestern Baltic and end the league's economic control there. The league's members raised an armed force that defeated the Danes decisively in 1368, and in the Peace of Stralsund (1370) Denmark was forced to recognize the league's supremacy in the Baltic.
In the 14th century the Hanseatic League claimed a membership of about 100 towns, mostly German. Though basically a mercantile rather than a political organization, the league tried to ensure peace and order at home; warfare between member towns, civic strife within towns, and robbery on the roads were all suppressed as far as possible. The league had no constitution and no permanent army, navy, or governing body except for periodic assemblies (diets). These were convened less and less frequently from the early 15th century, as the towns' peculiar and regional interests began to outweigh their common concerns.
The Hanseatic League declined partly because it lacked any centralized power with which to withstand the new and more powerful nation-states forming on its borders. Lithuania and Poland were united in 1386; Denmark, Sweden, and Norway formed a union in 1397; and Ivan III of Moscow closed the Hanseatic trading settlement at Novgorod in 1494. The Dutch were growing in mercantile and industrial strength, and in the 15th century they were able to oust German traders from Dutch domestic markets and the North Sea region as a whole. New maritime connections between the Baltic and Mediterranean seas and between the Old World and the Americas caused a gradual diversion of trade westward to the great Atlantic ports. By the mid-16th century, Dutch ships had even won control of the carrying trade from the Baltic to the west, dealing a serious blow to Lübeck. The league died slowly as England contested with the Netherlands for dominance in northern European commerce and Sweden emerged as the chief commercial power in the Baltic Sea region. The Hanseatic League's diet met for the last time in 1669.