He was born at Tveter farm in Asker as a son of Bent Holtsmark and his wife Anne Elisabeth Gabrielsen.

[1] His book Husdyrlære, a textbook on livestock, came in 1897 and was reprinted fourteen times, last in 1961.

[8] Also, he contributed to the newspapers and magazines Budstikken, Dagbladet, Verdens Gang, Tidens Tegn and Allers with writings on agriculture.

[9] He was later re-elected in 1915 and 1918 to serve a further two parliamentary terms, this time for the Liberal Left Party.

From 1927 to 1936 he worked as director and chair of Norges Hypotekbank, and he was also a member of several public boards, agencies and committees.