What was the name of the medieval trade federation of Northern European cities?

The medieval trade federation of Northern European cities was the Hanseatic League.

The Hanseatic League, also called the Hansa, was a loose commercial and defensive network rather than a centralized kingdom or modern government. It grew from trading partnerships among German merchants and towns during the 12th and 13th centuries, with Lübeck becoming its leading center. The League eventually connected nearly 200 settlements around the North and Baltic seas.

Hanseatic merchants traded goods such as timber, grain, wax, furs, herring, salt, and metals. In return, northern ports supplied cloth, manufactured goods, and other commodities. The League also operated privileged trading posts, known as kontors, in places including London, Bruges, Bergen, and Novgorod.

The name can be confused with the Lombard League, a political alliance of northern Italian cities that opposed imperial authority. The Hanseatic League was primarily a commercial network, though its collective power allowed it to negotiate privileges, impose blockades, and sometimes wage war.