Admiral William Carnegie, 7th Earl of Northesk was a British naval officer who served during the American Revolutionary War, French Revolutionary War, and Napoleonic Wars. While in command of HMS Monmouth he was caught in the Nore Mutiny of 1797 and was the officer selected to relay the demands of the mutineers to George III. He most notably served as third-in-command of the Mediterranean Fleet at the Battle of Trafalgar in HMS Britannia. He later became Rear-Admiral of the United Kingdom and Commander-in-Chief, Plymouth.

HMS Monmouth was a 64-gun third rate ship of the line of the Royal Navy, launched on 23 April 1796 at Rotherhithe. She had been designed and laid down for the East India Company, but the Navy purchased her after the start of the French Revolutionary War. She served at the Battle of Camperdown and during the Napoleonic Wars. Hulked in 1815, she was broken up in 1834.