In 1897, Rosenberg was awarded the degree of
Dr.Jur. and entered the Prussian judicial service, in which he was promoted to
Assessor in 1903. That year he transferred to the foreign service (
Auswärtiges Amt, AA). In 1910, Rosenberg became the head of the Balkans department at the AA, and in 1912 was promoted to
Vortragender Rat. During the
First World War, he was a member of the German delegation
negotiating with the Soviet Union at Brest-Litowsk and with
Romania at Bucharest. In 1918–1919, he was at the German Embassy to Switzerland at Bern. In 1919, Rosenberg became
Dirigent—head of the political department of the AA. In 1920–22, he was Ambassador at Vienna, and in 1922 briefly at Copenhagen. He was
Foreign Minister of Germany from November 1922 to August 1923 in the cabinet of chancellor
Wilhelm Cuno. From 1924 to 1933, he was Ambassador at Stockholm and then served from 1933 to 1935 as ambassador in
Ankara. In 1935, he was given an indefinite leave (
im einstweiligen Ruhestand). == Personal life ==