Fall of Berlin (1806) in the context of Treaty of Tilsit

The War of the Fourth Coalition (French: Guerre de la Quatrième Coalition) was a war spanning 1806–1807 that saw a multinational coalition fight against Napoleon's French Empire, subsequently being defeated. The main coalition partners were Prussia and Russia with Saxony, Sweden, and Great Britain also contributing. Excluding Prussia, some members of the coalition had previously been fighting France as part of the Third Coalition, and there was no intervening period of general peace. On 9 October 1806, Prussia declared war on France and joined a renewed coalition, fearing the rise in French power after the defeat of Austria and establishment of the French-sponsored Confederation of the Rhine in addition to having learned of French plans to cede Prussian-desired Hanover to Britain in exchange for peace. Prussia and Russia mobilized for a fresh campaign with France, massing troops in Saxony.

Napoleon decisively defeated the Prussians in an expeditious campaign that culminated at the Battle of Jena–Auerstedt on 14 October 1806. French forces under Napoleon occupied Prussia, pursued the remnants of the shattered Prussian Army, and captured Berlin. They then advanced all the way to East Prussia, Poland and the Russian frontier, where they fought an inconclusive battle against the Russians at the Battle of Eylau on 7–8 February 1807. Napoleon's advance on the Russian frontier was briefly checked during the spring as he revitalized his army with fresh supplies. Russian forces were finally crushed by the French at the Battle of Friedland on 14 June 1807, and three days later Russia asked for a truce.

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.

The Berlin Decree was issued in Berlin by Napoleon on November 21, 1806, after the French success against Prussia at the Battle of Jena, which led to the Fall of Berlin. The decree was issued in response to the British Order-in-Council of 16 May 1806 by which the Royal Navy instituted a blockade of all ports from Brest to the Elbe.

The decree proclaimed that "the British Isles are declared to be in a state of blockade" and forbade all correspondence or commerce with Great Britain. All British subjects found in the territory of France or its allies were to be arrested as prisoners of war and all British goods or merchandise seized. Any vessel found contravening the decree and landing in a continental port from a port of Britain or its colonies was to be treated as if it were British property and therefore liable to confiscation, along with all of its cargo.