 A career army officer, Prince Sadanaru entered the military academy in 1873 and fought as a lieutenant in the Satsuma Rebellion.Promoted to captain in 1878, he studied military tactics at the École Spéciale Militaire de Saint-Cyr in France and later in Germany in the 1870s.Upon his return to Japan, he was promoted to major in 1881 and advocated the establishment of a Japanese version of an army General Staff based on the Prussian model.