|Died||July 26, 1990 (aged 85–86)
|Service/branch||United States Navy|
|Years of service||1926–1965|
|Commands held||Missouri (BB-63)|
|Battles/wars||World War II
He grew up in Wellston, Ohio, the grandson of the city's first physician and son of the editor of the Wellston Telegram. He had a brother, George R., and a sister, Janet (later Mrs. Hiram Callahan). Sylvester attended the United States Naval Academy, and graduated among the top of his class in 1926.
Joining the fleet in 1926, Sylvester served in 1937 as flag lieutenant to Admiral Harry E. Yarnell, commander of the U.S. Asiatic Fleet, and married Yarnell's daughter Ruth. Much of his career was spent in the Pacific or East Asia, including postings to Shanghai, Tsingtao, Hong Kong and the Philippines. He served as commanding officer of the Missouri (BB-63) from 18 October 1951 to 4 September 1952 while the battleship was serving as flagship to Rear Admiral James L. Holloway, Jr., the commander of the cruiser force, Atlantic Fleet between deployments to the Korean War. Promoted to Rear Admiral in 1953, he was made special assistant to the chief of the Armed Forces Special Weapons Project in California. In 1955 Sylvester served as Task Force commander for Operation Wigwam, a test of an underwater detonation of a nuclear bomb. He served as Commander, Amphibious Forces, Pacific Fleet, from 1958 to 1960. From 1960 to 1965 he served as Deputy Chief of Naval Operations for Logistics, and retired in 1965 with the rank of Vice Admiral.
His first wife was Ruth Yarnell Sylvester, who died in 1948. His second wife was Geraldine Clark Sylvester. One of his sons would go on to attend the Naval Academy, as well as two grandsons. A second son, John Sylvester, Jr., would join the Foreign Service and, driven by the family connection to East Asia, serve a variety of tours in Japan and South East Asia in the 1960s.
- Clark G. Reynolds, Famous American Admirals (Annapolis: Naval Institute Press, 2002): 391.
- Description of John Sylvester, Jr., in Susan Sheehan and Howard B. Means, The Banana Sculptor, the Purple Lady and the All-Night Swimmer (New York: Simon & Schuster, 2002): 269-270.
- "John Sylvester, 86, Dies; Retired Navy Vice Admiral". The Washington Post. 27 July 1990. Retrieved 13 November 2010.