Isoroku_Yamamoto Fleet Admiral (4 April 1884 – 18 April 1943) was the commander-in-chief of the Combined Fleet during World War II, a graduate of the Imperial Japanese Naval Academy and a student of the U.S. Naval War College and of Harvard University (1919–1921). Yamamoto held several important posts in the Imperial Japanese Navy, and undertook many of its changes and reorganizations, especially its development of naval aviation.