He was a student at the outset of World War II and subsequently during the occupation of Norway by Nazi Germany.
He was arrested in Trondheim by the Nazi authorities on 2 November 1943, and was imprisoned at Falstad, then moved to Grini where he sat from 22 September 1944 to the liberation on 8 May 1945.
[2][3] He started his journalistic career in 1945 in Arbeider-Avisa, took the Master of Science degree in Chicago in 1947 and was hired as subeditor in Bergens Arbeiderblad in 1949.
[6] He left this position in the summer of 1966, and was succeeded by Jahn Otto Johansen, at that time the only permanent foreign correspondent of Dagsrevyen.
[7] Øisang was hired as chief editor of the Norwegian Broadcasting Corporation news department.