Ostróda

Ostróda lies on the Drwęca River in western Masuria. The town developed at the site of an Old Prussian settlement, where the Teutonic Order erected a wooden fortification around 1270. A stone castle replaced it between 1349 and 1370, and the town became a regional centre of the Order. After the Battle of Grunwald in 1410 it briefly came under Polish control before the knights regained it.

Following the Thirteen Years' War, Ostróda formed part of the Teutonic territory held as a Polish fief. From 1525 it belonged to Ducal Prussia. Swedish troops briefly occupied the town in 1628, and in 1807 Napoleon used its castle as his headquarters for several weeks.