The Confederation of Cologne (Danish: Kølner Konføderationen) was a medieval military alliance formed to combat the Kingdom of Denmark.

[1] Though originally only meant as a method of containing the growing Danish threat, the Confederation would remain intact for another 15 years after the signing of the Treaty of Stralsund, which concluded the Danish-Hanseatic War of 1361-1370.

Departure dates for cities throughout the Baltic and North Sea were also decided upon, to ensure the combined Confederate navy could assemble in the Oresund for a final assault on Denmark.

Bremen and Hamburg, for example, were exhausted due to previous wars, and refused to provide any military support, though financial aid was granted.

There was no reason to keep a military alliance together anymore, because the Danish king at the time was loyal to the Hanseatic League (due to the terms of the Treaty of Stralsund).

Despite it not being a permanent model for future Hanseatic agreements, it nonetheless was considered an impressive alliance, and multiple groups in the 15th century attempted to replicate it, with no success.