The Treaty of Salynas is signed between Grand Duke of Lithuania Vytautas the Great and the Teutonic Knights, who received Samogitia.

The Treaty of Salynas (German: Frieden von Sallinwerder, Lithuanian: Salyno sutartis) was a peace treaty signed on 12 October 1398 by Vytautas the Great, the Grand Duke of Lithuania, and Konrad von Jungingen, the Grand Master of the Teutonic Knights. It was signed on an islet of the Neman River, probably between Kulautuva and the mouth of the Nevėžis River. It was the third time, after the Treaty of Königsberg (1384) and Treaty of Lyck (1390), that Vytautas promised Samogitia to the Knights. The territory was important to the Knights as it physically separated the Teutonic Knights in Prussia from its branch in Livonia. It was the first time that the Knights and Vytautas attempted to enforce the cession of Samogitia. However, it did not solve the territorial disputes over Samogitia and they dragged on until the Treaty of Melno in 1422.