The English admiral John Rushworth Jellicoe, 1st Earl Jellicoe (1859-1935), was commander in chief of the British Grand Fleet during the first half of World War I.

Born on Dec. 5, 1859, at Southampton, John Jellicoe was the heir to a long naval tradition. Before he was 13 years old, Jellicoe was in the navy training to be an officer, and 2 years later he was a midshipman on a 2 1/2-year cruise of the sailing vessel New-castle. In 1877 he was with the fleet at the Dardanelles during the Russo-Turkish War and, as the result of his excellent record there, was sent to the Royal Naval College at Greenwich.

Until 1898 Jellicoe was assigned to various posts, including gunnery and torpedo schools and sea duty. He became closely associated with the naval reforms and innovations of John French. In 1898 he was sent to East Asian waters as chief of staff to Adm. Seymour. There...