In 1907, Haber became lecturer Council in the Imperial Colonial Office to Berlin and received his appointment to the secret Oberregierungsrat in 1910.

Together with 11 other German prisoners of war, he was brought to Sydney on the captured steamer SMS Komet and interned on 29 October in a camp at Holsworthy, New South Wales.

[1] In Berlin, he continued as the Acting-Governor of German New Guinea and was officially appointed Governor on 14 December 1917, as Hahl was declared unfit by Wilhelm Solf, the Imperial Colonial Secretary.

Both Emperor Wilhelm II and Erich Ludendorff believed that the continuation of a Governorship during the war was a hasty and badly conceived decision, as the Pacific colony would play no further role for Germany.

After leaving the Imperial service in 1923, he assumed a teaching position at the Bergakademie Clausthal and received an Honorary Professorship in 1924, remaining there until 1927.