Admiral of the Fleet Sir Caspar John GCB (22 March 1903 – 11 July 1984) was a senior Royal Navy officer who served as First Sea Lord from 1960 to 1963.
He was a pioneer in the Fleet Air Arm and fought in the Second World War in a cruiser taking part in the Atlantic convoys, participating in the Norwegian campaign and transporting arms around the Cape of Good Hope to Egypt for use in the western desert campaign.