As part of the War of the Fourth Coalition the Prussian fortress at Graudenz in West Prussia in the Prussian Partition of Poland (now Grudziądz, Poland) was besieged by forces of the French Empire and its allies.

The garrison, commanded by General Wilhelm René de l'Homme de Courbière, withheld blockade and siege for some 11 months, long past the formal Peace of Tilsit.

The French abandoned the siege after the borders between Prussia and the new Duchy of Warsaw were defined; Graudenz/Grudziądz staying a Prussian possession until Poland regained independence after World War I.

The Polish 2nd, 4th and 7th Infantry Regiments took part in the battle on the side of Napoleon.

[3] This article about a battle of the Napoleonic Wars is a stub.