Admiral Sir William Milbourne James, was a British naval commander, politician and author. He served in the Royal Navy from the early 20th century to the Second World War. During the First World War, he was an integral part of the Naval Intelligence Division in its early years.

Admiral Sir William Reginald Hall, known as Blinker Hall, was the British Director of Naval Intelligence (DNI) from 1914 to 1919. Together with Sir Alfred Ewing he was responsible for the establishment of the Royal Navy's codebreaking operation, Room 40, which decoded the Zimmermann telegram, a major factor in the entry of the United States into World War I.