Cornwall was a British County-class heavy cruiser, pennant 56. Devonport Dockyard launched her on 11 March 1926 and the Navy commissioned her on 8 May 1928. Eight 8-inch guns, and the long range the County ships were built for.
On 8 May 1941, in the Indian Ocean, she caught the German raider Pinguin. Pinguin scored hits and fired torpedoes that missed. Cornwall sank her. Percival Manwaring was her captain.
In April 1942 she was with the Eastern Fleet. On 4 April she and Dorsetshire left Colombo. A floatplane from the cruiser Tone found them the next day, southwest of Ceylon. Dive bombers from Soryu and Hiryu attacked. Cornwall was hit and sank bow first. Manwaring was wounded in the shoulder and survived. Dorsetshire went down in the same attack. The two ships lost 424 men. The sinkings are not credited to one Japanese ship.
The cruiser Enterprise and the destroyers Paladin and Panther picked up survivors the next day.