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. After graduating from the university, he was a teacher at Kristiania Commerce School (1907) and Vestheim School (1908–1912). In 1913 he became chief editor of the conservative newspaper Morgenbladet, a post he held until 1919. He then focused on pursuing a political career, having been elected in the autumn of 1918. He returned to the press as editor of the magazine Ukens Revy from 1921 to 1929. Ukens Revy had been distinctively pro-German and anti-British during the First World War. 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".