The Mauritius campaign of 1809–1811 was a series of amphibious operations and naval actions fought to determine possession of the French Indian Ocean territories of Isle de France and Île Bonaparte during the Napoleonic Wars. The campaign lasted from the spring of 1809 until the spring of 1811, and saw both the Royal Navy and the French Navy deploy substantial frigate squadrons with the intention of disrupting or protecting trade from British India. In a war in which the Royal Navy was almost universally dominant at sea, the campaign is especially notable for the local superiority enjoyed by the French Navy in the autumn of 1810 following the British disaster at the Battle of Grand Port, the most significant defeat for the Royal Navy in the entire conflict. After their victory, the British