William Fisher was born in 1875, the son of Herbert Fisher, Vice-Warden of the Stannaries [Cornwall]; he married Cecilia, youngest daughter of F. Warre Cornish; they had one son and two daughters.

Fisher joined the Navy as a Cadet in 1888, being educated on HMS Britannia. He was promoted to Midshipman in 1890, then became Sub-Lieutenant in 1894, full Lieutenant in 1896, Commander in 1906 and Captain in 1912. In the First World War, Fisher commanded HMS St Vincent during the Battle of Jutland, then from 1917-18 served as Director of the Admiralty Anti-Submarine Division. After the war he became Chief of the Staff for the Mediterranean Fleet, (1919-22) and also Naval Aide de Camp to King George V, (1921-22). Following his promotion to Rear-Admiral in 1922, Fisher moved to be Chief of the Staff to the Atlantic Fleet, (1922-24), then Rear-Admiral of the 1st Battle Squadron, Mediterranean Fleet, (1924-25). He served as 4th Sea Lord from 1927 to 1928, then as a Vice-Admiral, became Deputy Chief of Naval Staff, (1928-30), Vice-Admiral commanding the 1st Battle Squadron and Second in Command of the Mediterranean Fleet, (1930-32). Fisher was made a full Admiral in 1932 and took over as Commander-in-Chief of the Mediterranean Fleet, (1932-36). His final position was as Commander-in-Chief, Portsmouth [Hampshire], from 1936 until his death on 24 June 1937.

Fisher's honours included: Officer of the Legion of Honour and Order of the Rising Sun of Japan, 3rd Class; United States Distinguished Service Medal; GCB, 1935; GCVO, 1935; KCB, 1929; CB 1918; CVO 1924; MVO 1908.