The Prussian Confederation is formed.

Prussian Confederation

Organization of Prussian nobles in opposition to the Teutonic Order (1440-66)

The Prussian Confederation was an organization formed on 21 February 1440 at Marienwerder by a group of 53 nobles and clergy and 19 cities in Prussia, to oppose the arbitrariness of the Teutonic Knights. It was based on an earlier similar organization, the Lizard Union…