Adriatic campaign of 1807–1814

The Adriatic campaign was a minor theatre of war during the Napoleonic Wars in which a succession of small British Royal Navy and Austrian Navy squadrons and independent cruisers harried the combined naval forces of the First French Empire, the Kingdom of Italy, the Illyrian Provinces and the Kingdom of Naples between 1807 and 1814 in the Adriatic Sea. Italy, Naples and Illyria were all controlled either directly or via proxy by the French Emperor Napoleon I, who had seized them at the Treaty of Pressburg in the aftermath of the War of the Third Coalition.

Control of the Adriatic brought numerous advantages to the French Navy, allowing rapid transit of troops from Italy to the Balkans and Austria for campaigning in the east and giving France possession of numerous shipbuilding facilities, particularly the large naval yards of Venice. From 1807, when the Treaty of Tilsit precipitated a Russian withdrawal from the Septinsular Republic, the French Navy held naval supremacy in the region. The Treaty of Tilsit also contained a secret clause that guaranteed French assistance in any war fought between the Russians and the Ottoman Empire. To fulfil this clause, Napoleon would have to secure his supply lines to the east by developing the French armies in Illyria. This required control of the Adriatic against increasingly aggressive British raiders. The Royal Navy decided to prevent these troop convoys from reaching Illyria and sought to break French hegemony in the region, resulting in a six-year naval campaign.

The campaign was not uniform in approach; British and French forces were limited by the dictates of the wider Mediterranean and global conflict, and consequently ship numbers fluctuated. Although numerous commanders held commands in the region, the two most important personalities were those of William Hoste and Bernard Dubourdieu, whose exploits were celebrated in their respective national newspapers during 1810 and 1811. The campaign between the two officers reached a climax at the Battle of Lissa in March 1811, when Dubourdieu was killed and his squadron defeated by Hoste in a celebrated action.

The events of 1811 gave the British dominance in the Adriatic for the remainder of the war. British and Greek expeditionary forces steadily captured fortified French islands and their raiding parties inflicted havoc on trade across the region. As a result, French plans against the Ottoman Empire were cancelled, La Grande Armée turning towards Russia. British forces continued operations until the advancing armies of the Sixth Coalition drove the French from the shores of the Adriatic in early 1814, British troops and marines assisting in the capture of several important French cities, including Fiume (Rijeka) and Trieste.