Frithjof Jacobsen (31 October 1843 – 12 February 1921) was a Norwegian military officer and sports official.
Jacobsen was born in Vaage Municipality to physician Nils Laurits Severin Jacobsen and Johanne Jørgensen.
He served as acting War Commissioner in Bodø from 1909 to 1910, and in Hamar from 1911 to 1916.
From 1904 to 1906 he chaired the sports association Centralforeningen for utbredelse af idræt.
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