[6] In 1349 Grand Master of the Teutonic Order Heinrich Dusemer founded a Franciscan Monastery there to commemorate his victory over the Prussians in the battle of Streba River.

[6] The war ended in 1466 with a peace treaty signed in Toruń, according to which the town became a part of Poland as a fief held by the Teutonic Knights.

[8] In 1490 Grand Master Johann von Tiefen restored (or founded, the sources are unclear) another Franciscan monastery in the town.

However, it was destroyed in 1519 in the course of Protestant Reformation, when the burghers converted to Protestantism and decided that such a small town is not able to bear the burden of sustaining two monasteries.

[6] The town finally recovered and by the end of 16th century Margrave Georg Friedrich considered moving the University of Königsberg to Wehlau, which however never materialised.

[9] In the Treaty of Wehlau signed in the town in 1657, Frederick William, Elector of Brandenburg, received sovereignty over the Duchy of Prussia.