Seven ships of the Royal Navy have been named HMS Cornwall after the Duchy of Cornwall. Cornwall's motto is onen hag oll (- Cornish), unus et omnes (- Latin), one and all - English).
HMS Cornwall (1761) was a 74-gun third-rate launched in 1761. She was damaged in action in 1780, and subsequently burnt as unserviceable.
HMS Cornwall was the name initially chosen for HMS Heir Apparent, a 74-gun third rate captured from the Danes in 1807, but the name was not used.
HMS Cornwall (1812) was a 74-gun third-rate launched in 1812. She was reduced to 50 guns in 1831, was renamed HMS Wellesley in 1869 and served as a school ship until broken up in 1874.
HMS Cornwall was a 74-gun third rate launched in 1815 as HMS Wellesley. She was renamed HMS Cornwall in 1868 when she became a school ship, and was sunk in 1940.