Which cities helped form the Hanseatic League?

The Hanseatic League was not founded by a single group of cities at one moment; rather, it emerged from the gradual coalescence of various associations of merchants and trading towns across northern Europe.1

The league’s origins are rooted in two primary regions:
* The West: Merchants from the Rhineland, particularly Cologne, were active in England and the Low Countries.1
* The East: German merchants established a monopoly in the Baltic Sea, using Lübeck as a central base.1

Key early alliances that paved the way for the league included:
* A 1210 agreement between Lübeck and Hamburg to share common laws.1
* A 1241 formal alliance between these two cities to combat piracy.1
* A 1259 agreement involving Lübeck, Rostock, Wismar, and Stralsund.1

Additionally, German merchants were instrumental in establishing or developing major trading centers such as Visby, Riga, Tallinn, Gdańsk, and Tartu.1