Hambro attended the middle school and high school his father had founded in Bergen. He took the
examen artium in 1902, and enrolled in
philology studies at the
Royal Frederick University. While studying, he took many excursions, working as translator, literary critic, part-time teacher and even participant on the research vessel
Michael Sars. He was involved in the
Norwegian Students' Society, which he chaired in 1908, 1909 and in the autumn of 1911. He chaired the
Conservative Students' Association in 1908, 1910 and 1911, and was also vice chairman of
Filologisk Forening in 1904. From 1910 to 1913 he was the secretary of the
Norse Federation, and edited its periodical from 1911 to 1916. He was also involved in
association football, chairing the club Akademisk FK and being vice chairman (in 1904) of the fledgling
Football Association of Norway. During the war, Hambro got entangled in British affairs. In January 1917, the United Kingdom had ceased its coal exports to Norway. During the negotiations between
Knudsen's Cabinet's representatives and the British legation in Kristiania, Hambro wrote an editorial in
Morgenbladet which suggested expulsion of the British diplomats if Norwegian needs were not met. British Foreign Secretary
Arthur Balfour met with the Norwegian ambassador in the UK, and demanded that Knudsen's Cabinet either deplore
Morgenbladet's statements or prosecute Hambro legally. Hambro's actions were defended by the Norwegian parliamentary opposition, including the Conservative Party. After some rounds of talks and negotiations, the whole case blew over. In the first phase of the First World War, Hambro had campaigned restlessly against Knudsen's Cabinet which he perceived as too weak to lead the country through a war. Hambro and
Morgenbladet was joined in this endeavor by
Tidens Tegn and to an extent
Aftenposten. Prime Minister
Gunnar Knudsen summoned a sitdown of himself and the three newspaper's editors, where he tried to calm their attacks. "The attempt failed completely", notes historian
Hans Fredrik Dahl. Hambro also marked himself as a critic of socialism. He reacted strongly against the
antimilitaristic policies of the socialists in Norway, and called for reactions against those who spread such "contamination" in print. In 1918, in the wake of the
Russian Revolution, Hambro suggested that the revolutionary socialist press be met with harsher regulations. He wrote in
Morgenbladet: "Perhaps our authorities should be more attentive towards the socially subversive agitation long practiced by our socialist leaders in writing and speech". On the other hand, he also criticized cases of actual censorship directed towards the workers' movement, among others during the secret military expedition to quell calamities in
Rjukan in May 1914. He chaired the boards of the
Conservative Press Association from 1913 to 1920,
Ukens Revy from 1919 to 1929, the
Norwegian News Agency from 1920 to 1946 (vice chairman 1918 to 1920), and the Norse Federation from 1923 to 1946 (board member 1913 to 1915, vice chairman 1915 to 1923). He was the vice chairman of
Det Nye Teater from 1928 to 1932, a board member of
Morgenbladet from 1921 to 1933 as well as of the
Institute for Comparative Research in Human Culture. ==Political career==