Robert Heriot Barclay (18 September 1786 – 8 May 1837) was a British naval officer who was engaged in the Napoleonic Wars, and its North American counterpart, the War of 1812. He was born at Cupar, Fife, Scotland, the son of the Rev. Peter Barclay DD & Margaret Dudingston. He entered the Royal Navy in 1798, aged 11. In 1805 he was promoted Lieutenant, and took part in the Battle of Trafalgar aboard HMS Swiftsure. He was subsequently appointed the second Lieutenant of the frigate HMS Diana, serving in the English Channel. In November 1809 he lost his left arm while leading a boarding attack on a French convoy.