An association of north German cities (Hanse Towns), formed in 1241 as a trading alliance. Cologne, which had enjoyed special trading privileges with England, was joined by other traders following an agreement between Hamburg and Lübeck (1241) and a Diet of 1260. The towns of the League dealt mainly in wool, cloth, linen, and silver. In the later Middle Ages the League, with about 100 member towns, was an independent political power with its own army and navy. It began to collapse in the early 17th century and only three major cities (Hamburg, Bremen, and Lübeck) remained in the League until it was finally broken up in the 19th century.