Thirteen Years’ War (1454 – 1466)
The Thirteen Years’ War was fought between the Polish-Lithuanian State and Prussian Confederation on the one side and the Monastic state of Teutonic Knights on the other from 1454 to 1466. The war started with an uprising of the Hanseatic cities under leadership of Hans von Baysen against the Teutonic Knights. Poland intervened in the struggle between the Prussian Confederation and the Teutonic Knights on Prussian appeal in 1454.
Financial resources were decisive for the outcome of the Thirteen Years’ War which was predominantly fought by the mercenary troops. When the Teutonic Knights run out of funds its mercenaries offered their fortresses to their adversaries who had less financial difficulties. The Poles decisively defeated the Teutonic Knights in the Battle of Swiecino (Schwetz) in 1462. Many historians consider the Battle of Swiecino the turning point of the Thirteen Years’ War but the Teutonic Knights managed to hold out until 1466 when they finally went out of funds. They had to sign the second Treaty of Torun which resulted in the collapse of the Monastic state of the Teutonic Knights. The Teutonic Knights were forced to cede West Prussia and Pomerelia to Poland, while the remaining East Prussia became a Polish vassal state.