Haaken Christensen worked for the advertising agency Høydahl-Ohme from 1930. This agency was owned by the authors of the comic series 'Nils og Blåmann', Ivar Mauritz-Hansen and Sigurd Winsnes. Mauritz-Hansen suggested that Christensen should start a comic series of his own. This resulted in the series about the bear 'Brumle', that appeared in Illustrert Familieblad from 1935 to 1958. 21 books appeared from 1935 to 1956.