The naval Battle of Monte Santiago was a naval battle on 7–8 April 1827, between the Argentine Navy and Brazilian Imperial Navy, during the Cisplatine War. It was a decisive Brazilian victory, with the allied forces losing its best ships. The battle is highlighted by Argentine historians as one of the most courageous and ferocious naval encounters in the country's history. On that day, Sgt. Mayor Francis Drummond (engaged to Admiral Brown's daughter Elisa) died on deck, firing his marooned ship's cannons instead of retreating.