Thommessen started working for
Dagbladet in 1875. He worked for
Verdens Gang from 1876, and as editor-in-chief from 1878 to 1910. Under his leadership
Verdens Gang became the main publication for the
Liberal Party, and a modern newspaper of high standard. The leadership period included the period of political turmoil in the 1880s. The newspaper supported the
Liberal Party and
Johan Sverdrup, and their endeavors to form a cabinet. Thommessen frequently corresponded with the writer
Bjørnstjerne Bjørnson at this time, and was also a friend of
Lars Holst,
Oda Krohg,
Mathilde Schjøtt as well as
Maren,
Ossian and
Ernst Sars. Thommessen was a controversial person, and he is targeted in
Knut Hamsun's novel
Redaktør Lynge (1893), which is regarded as a personal attack on Thommessen, one of the strongest in the history of Norwegian literature. The novel still received good reviews in
Verdens Gang. He was a member of the
Norwegian Association for Women's Rights. In the
interwar period Thommessen was known for his
anti-communism. He was skeptic to the
Norwegian Parliament, and advocated a strong bourgeois leadership as a leading member of
Fedrelandslaget. Thommessen also wrote several books. He died in 1942, 91 years old, surviving both his sons. ==References==