Henry Edward Diesen (3 April 1883 – 7 January 1953) was a Norwegian naval officer.
He was born in Trondhjem as a son of telegrapher Edward Diesen (1852–1909) and Johanne Christophine Stenersen (1855–1936). He was a first cousin of Emil Diesen and Andreas Melchior Seip Diesen, and a first cousin once removed of Andreas’s son Ernst Diesen.
He was a naval officer from 1903, graduated from the Norwegian Naval Academy in 1905 and was promoted to Premier Lieutenant in 1906. He worked in the merchant fleet from 1906 to 1908 and 1909 to 1911. From 1912 to 1913, he studied at the Berlin Institute of Technology. He served in the neutral Royal Norwegian Navy during World War I, and was promoted to Captain in 1917. His last service on a ship was as second-in-command of HNoMS Tordenskjold in 1929.
He lived in Borre near Karljohansvern. Here he edited the newspaper Hortens Avis from 1919 to 1920 and was a member of the executive committee of Borre municipal council from 1920 to 1923. Since November 1907 he was married to Caroline Elisabeth Fretheim (1886–1968).
From 1930 to 1936, Diesen was the second-in-command at the Navy Mining School. He was promoted to Commander in 1936. In 1937 he was appointed as chief of the Third Naval Defence District (Northern Norway), and in 1938 he became Commanding Admiral in Norway. He was also promoted to Rear Admiral. In 1940 Norway was invaded by Nazi Germany. Two months later, Diesen embarked the ship HNoMS Fridtjof Nansen with which he fled the country. The vessel left Norway on 10 June, arrived at Tórshavn, in the Faroe Islands, on 13 June and later sailed to the United Kingdom where she was made war ready. From now the Royal Norwegian Navy was used in the Allied warfare. He left his position as Commanding Admiral in August 1941, over disagreements with the government, and served in the United States until 1944. From 1945 to 1947 he was the chief of Marinekommando Vestlandet.
- Kristiansen, Tom. "Henry Diesen". In Helle, Knut. Norsk biografisk leksikon (in Norwegian). Oslo: Kunnskapsforlaget. Retrieved 7 October 2010.
- Henriksen, Petter, ed. (2007). "Diesen – slekt fra Nord-Odal". Store norske leksikon (in Norwegian). Oslo: Kunnskapsforlaget. Retrieved 14 October 2010.
- Henriksen, Petter, ed. (2007). "Henry Edward Diesen". Store norske leksikon (in Norwegian). Oslo: Kunnskapsforlaget. Retrieved 7 October 2010.
- Sivertsen, Svein Carl (ed.) (2001). Sjøforsvaret dag for dag 1814–2000 (in Norwegian). Hundvåg: Sjømilitære Samfund ved Norsk Tidsskrift for Sjøvesen. p. 139. ISBN 82-92217-03-7.
|Commanding Admiral in Norway