John Rushworth Jellicoe, 1st Earl Jellicoe (born December 5, 1859, Southampton, Hampshire, England—died November 20, 1935, Kensington, London) was a British admiral of the fleet who commanded at the crucial Battle of Jutland (May 31, 1916) during World War I.
The son of a captain in the mercantile marine, Jellicoe was educated at Rottingdean and entered the Royal Navy as a naval cadet in 1872. He joined the Royal Naval College in 1883 and became a gunnery expert, and in 1888 he was appointed to the Admiralty as an assistant to the director of naval ordnance. In 1891 he was promoted to commander and shortly afterward was appointed to HMS Victoria of the Mediterranean fleet. In 1898 Jellicoe was appointed to the command of HMS Centurion, of the China station, and took part in the expedition to relieve the legations in Beijing during the Boxer Rebellion in 1900. From 1902 to 1914 he held a variety of posts in the Admiralty and in the fleet, during which time he improved and systematized the Royal Navy’s methods for aiming the big guns of its warships.
On the eve of World War I, Jellicoe was sent to join the home fleet at Scapa as second in command under Admiral Sir George Callaghan and was soon appointed commander in chief with acting rank of admiral. He was confirmed in his rank in March 1915 and for two years organized and trained the grand fleet and kept it ready for action. His command was put to the test at the Battle of Jutland. Although his tactics were severely criticized at the time, it is now accepted that he achieved a strategic victory that left the German high seas fleet ineffective during the remainder of the war. Toward the end of 1916 Jellicoe left his last command afloat to become first sea lord of the Admiralty. During the next year his efforts to combat the new German submarine campaign were not effective until the convoy system was adopted at the insistence of the prime minister, David Lloyd George, who was responsible for Jellicoe’s retirement from the Admiralty at the end of 1917. After the armistice, Jellicoe was sent on a special mission to visit the dominions and advise on the postwar organization of their navies. Promoted to admiral of the fleet in 1919, he became governor of New Zealand in 1920.
For his services in World War I, Jellicoe was raised to the peerage as Viscount Jellicoe of Scapa in 1918. On his return from New Zealand and in recognition of his services as governor, he was created an earl and Viscount Brocas of Southampton in 1925. He published The Grand Fleet, 1914–16, Its Creation, Development and Work (1919) and The Crisis of the Naval War (1921).