politician member of the Parliament of Norway
He was elected to the Norwegian Parliament from the Market towns of Østfold and Akershus counties in 1945, but was not re-elected in 1949 as the Communist Party dropped from 11 to 0 seats in Parliament. Contrary to most Communist Party representatives in the Parliament, Jenssen had higher education. He worked with libraries and as a teacher.
Markussen was a member of the executive committee of Fredrikstad city council during the terms 1919–1922 and 1922–1925.