Sovetsk, Kaliningrad Oblast in the context of Treaty of Tilsit

The Treaties of Tilsit (French: Traités de Tilsit), also collectively known as the Peace of Tilsit (German: Friede von Tilsit; Russian: Тильзитский мир, romanized: Tilzitski mir), were two peace treaties signed by French Emperor Napoleon in the town of Tilsit in July 1807 in the aftermath of his victory at Friedland, at the end of the War of the Fourth Coalition. The first was signed on 7 July, between Napoleon and Russian Emperor Alexander I, when they met on a raft in the middle of the Neman river. The second was signed with Prussia on 9 July. The treaties were made at the expense of King Frederick William III of Prussia, who had already agreed to a truce on 25 June after the Grande Armée had captured Berlin and pursued him to the easternmost frontier of his realm.

In Tilsit, Prussia ceded about half of its pre-war territories. From these territories, Napoleon had created French client states, which were formalized and recognized at Tilsit: the Kingdom of Westphalia, the Duchy of Warsaw and the Free City of Danzig; the other ceded territories were awarded to existing French client states and to Russia.