The aim of this paper is to examine the conduct of war at sea at the time of Napoleon and to explore how subsequent interpretations of this war have influenced the development of maritime strategy and, by extension, of naval policy from the late nineteenth century through to the present day. The title identifies the area of enquiry as war at sea in the age of Napoleon, an unusual choice given the Corsican’s very limited understanding of the challenges and opportunities presented by the use of naval forces. Maritime historians, and particularly those from Britain, are more likely to write about the war at sea during the age of Nelson, the greatest admiral of his time, described by one recent British biographer as ‘a national secular deity, the god of war for troubled times, the last resort against overwhelming odds, guardian against tyranny’.2 The title was, however, chosen for a reason. It was chosen to emphasize that war at sea is about more than just war at sea. Events at sea matter only insofar as they have an impact on the land as it is there that people live and where great issues between nations are decided. One cannot understand war at sea unless one understands the role played by fleets, squadrons and ships, but this on its own is not enough. A mature understanding of the role of maritime power in these wars requires one to look at more than the clash of great fleets and to question the extent to which events at sea had an impact on the outcome of the war.