After the war, Abe graduated from the Imperial Japanese Army Academy in November 1897. Commissioned a second lieutenant the following 27 June, he was promoted to lieutenant in November 1900 and attended the Army Artillery School, graduating in December 1901. Promoted to captain in November 1903, he enrolled in the 19th class of the Army War College, graduating in November 1907. Ultranationalist General Araki Sadao was one of his classmates. He was promoted to major in December 1908, becoming an instructor at the Army War College in September 1909. In November 1910, he was posted to the German Empire as a military attache' at the Japanese embassy, and became a supplementary attaché at the embassy in Vienna in February 1913.